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nfcorpus-qrel-MED-1474 | Generate text that best answers this question: saturated fat | Free fatty acids and skeletal muscle insulin resistance.
PURPOSE OF REVIEW: Acute exposure to fatty acids causes insulin resistance in muscle, and excess dietary lipid and obesity are also strongly associated with muscle insulin resistance. Relevant mechanisms, however, are still not fully elucidated. Here we examine the latest evidence as to why lipids might accumulate in muscle and the possible mechanisms for lipid-induced insulin resistance. RECENT FINDINGS: Muscle lipid metabolites such as long chain fatty acid coenzyme As, diacylglycerol and ceramides may impair insulin signalling directly. Crosstalk between inflammatory signalling pathways and insulin signalling pathways, mitochondrial dysfunction and oxidative stress have also been put forward as major contributors to the development or maintenance of lipid-induced insulin resistance in muscle. Several animal models with gene deletions in pathways of fatty acid synthesis and storage also show increased metabolic rate, reduced intramuscular lipid storage and improved insulin action when challenged with a high lipid load. SUMMARY: Studies in genetic and dietary obese animal models, genetically modified animals and humans with obesity or type 2 diabetes suggest plausible mechanisms for effects of fatty acids, lipid metabolites, inflammatory pathways and mitochondrial dysfunction on insulin action in muscle. Many of these mechanisms, however, have been demonstrated in situations in which lipid accumulation (obesity) already exists. Whether the initial events leading to muscle insulin resistance are direct effects of fatty acids in muscle or are secondary to lipid accumulation in adipose tissue or liver remains to be clarified. |
nfcorpus-qrel-MED-1470 | Generate text that best answers this question: saturated fat | Intramyocellular lipid concentrations are correlated with insulin sensitivity in humans: a 1H NMR spectroscopy study.
Recent muscle biopsy studies have shown a relation between intramuscular lipid content and insulin resistance. The aim of this study was to test this relation in humans by using a novel proton nuclear magnetic resonance (1H NMR) spectroscopy technique, which enables non-invasive and rapid (approximately 45 min) determination of intramyocellular lipid (IMCL) content. Normal weight non-diabetic adults (n = 23, age 29+/-2 years. BMI = 24.1+/-0.5 kg/m2) were studied using cross-sectional analysis. Insulin sensitivity was assessed by a 2-h hyperinsulinaemic (approximately 450 pmol/l)-euglycaemic (approximately 5 mmol/l) clamp test. Intramyocellular lipid concentrations were determined by using localized 1H NMR spectroscopy of soleus muscle. Simple linear regression analysis showed an inverse correlation (r = -0.579, p = 0.0037) [corrected] between intramyocellular lipid content and M-value (100-120 min of clamp) as well as between fasting plasma non-esterified fatty acid concentration and M-value (r = -0.54, p = 0.0267). Intramyocellular lipid content was not related to BMI, age and fasting plasma concentrations of triglycerides, non-esterified fatty acids, glucose or insulin. These results show that intramyocellular lipid concentration, as assessed non invasively by localized 1H NMR spectroscopy, is a good indicator of whole body insulin sensitivity in non-diabetic, non-obese humans. |
nfcorpus-qrel-MED-1471 | Generate text that best answers this question: saturated fat | Overnight lowering of free fatty acids with Acipimox improves insulin resistance and glucose tolerance in obese diabetic and nondiabetic subjects.
Obesity is commonly associated with elevated plasma free fatty acid (FFA) levels, as well as with insulin resistance and hyperinsulinemia, two important cardiovascular risk factors. What causes insulin resistance and hyperinsulinemia in obesity remains uncertain. Here, we have tested the hypothesis that FFAs are the link between obesity and insulin resistance/hyperinsulinemia and that, therefore, lowering of chronically elevated plasma FFA levels would improve insulin resistance/hyperinsulinemia and glucose tolerance in obese nondiabetic and diabetic subjects. Acipimox (250 mg), a long-acting antilipolytic drug, or placebo was given overnight (at 7:00 P.M., 1:00 A.M., 7:00 A.M.) to 9 lean control subjects, 13 obese nondiabetic subjects, 10 obese subjects with impaired glucose tolerance, and 11 patients with type 2 diabetes. Euglycemic-hyperinsulinemic clamps and oral glucose tolerance tests (75 g) were performed on separate mornings after overnight Acipimox or placebo treatment. In the three obese study groups, Acipimox lowered fasting levels of plasma FFAs (by 60-70%) and plasma insulin (by approximately 50%). Insulin-stimulated glucose uptake during euglycemic-hyperinsulinemic clamping was more than twofold higher after Acipimox than after placebo. Areas under the glucose and insulin curves during oral glucose tolerance testing were both approximately 30% lower after Acipimox administration than after placebo. We conclude that lowering of elevated plasma FFA levels can reduce insulin resistance/hyperinsulinemia and improve oral glucose tolerance in lean and obese nondiabetic subjects and in obese patients with type 2 diabetes. |
nfcorpus-qrel-MED-1472 | Generate text that best answers this question: saturated fat | Rapid impairment of skeletal muscle glucose transport/phosphorylation by free fatty acids in humans.
The initial effects of free fatty acids (FFAs) on glucose transport/phosphorylation were studied in seven healthy men in the presence of elevated (1.44 +/- 0.16 mmol/l), basal (0.35 +/- 0.06 mmol/l), and low (<0.01 mmol/l; control) plasma FFA concentrations (P < 0.05 between all groups) during euglycemic-hyperinsulinemic clamps. Concentrations of glucose-6-phosphate (G-6-P), inorganic phosphate (Pi), phosphocreatine, ADP, and pH in calf muscle were measured every 3.2 min for 180 min by using 31P nuclear magnetic resonance spectroscopy. Rates of whole-body glucose uptake increased similarly until 140 min but thereafter declined by approximately 20% in the presence of basal and high FFAs (42.8 +/- 3.6 and 41.6 +/- 3.3 vs. control: 52.7 +/- 3.3 micromol x kg(-1) x min(-1), P < 0.05). The rise of intramuscular G-6-P concentrations was already blunted at 45 min of high FFA exposure (184 +/- 17 vs. control: 238 +/- 17 micromol/l, P = 0.008). At 180 min, G-6-P was lower in the presence of both high and basal FFAs (197 +/- 21 and 213 +/- 18 vs. control: 286 +/- 19 micromol/l, P < 0.05). Intramuscular pH decreased by -0.013 +/- 0.001 (P < 0.005) during control but increased by +0.008 +/- 0.002 (P < 0.05) during high FFA exposure, while Pi rose by approximately 0.39 mmol/l (P < 0.005) within 70 min and then slowly decreased in all studies. In conclusion, the lack of an initial peak and the early decline of muscle G-6-P concentrations suggest that even at physiological concentrations, FFAs primarily inhibit glucose transport/phosphorylation, preceding the reduction of whole-body glucose disposal by up to 120 min in humans. |
nfcorpus-qrel-MED-1473 | Generate text that best answers this question: saturated fat | Mechanism of free fatty acid-induced insulin resistance in humans.
To examine the mechanism by which lipids cause insulin resistance in humans, skeletal muscle glycogen and glucose-6-phosphate concentrations were measured every 15 min by simultaneous 13C and 31P nuclear magnetic resonance spectroscopy in nine healthy subjects in the presence of low (0.18 +/- 0.02 mM [mean +/- SEM]; control) or high (1.93 +/- 0.04 mM; lipid infusion) plasma free fatty acid levels under euglycemic (approximately 5.2 mM) hyperinsulinemic (approximately 400 pM) clamp conditions for 6 h. During the initial 3.5 h of the clamp the rate of whole-body glucose uptake was not affected by lipid infusion, but it then decreased continuously to be approximately 46% of control values after 6 h (P < 0.00001). Augmented lipid oxidation was accompanied by a approximately 40% reduction of oxidative glucose metabolism starting during the third hour of lipid infusion (P < 0.05). Rates of muscle glycogen synthesis were similar during the first 3 h of lipid and control infusion, but thereafter decreased to approximately 50% of control values (4.0 +/- 1.0 vs. 9.3 +/- 1.6 mumol/[kg.min], P < 0.05). Reduction of muscle glycogen synthesis by elevated plasma free fatty acids was preceded by a fall of muscle glucose-6-phosphate concentrations starting at approximately 1.5 h (195 +/- 25 vs. control: 237 +/- 26 mM; P < 0.01). Therefore in contrast to the originally postulated mechanism in which free fatty acids were thought to inhibit insulin-stimulated glucose uptake in muscle through initial inhibition of pyruvate dehydrogenase these results demonstrate that free fatty acids induce insulin resistance in humans by initial inhibition of glucose transport/phosphorylation which is then followed by an approximately 50% reduction in both the rate of muscle glycogen synthesis and glucose oxidation. |
nfcorpus-qrel-MED-1475 | Generate text that best answers this question: saturated fat | Effects of an overnight intravenous lipid infusion on intramyocellular lipid content and insulin sensitivity in African-American versus Caucasian adolescents
Objective To explain the predisposition for insulin resistance among African American (AA) adolescents, this study aimed to: 1) examine changes in intramyocellular lipid content (IMCL), and insulin sensitivity with intralipid (IL) infusion; and 2) determine whether the increase in IMCL is comparable between AA and Caucasian adolescents. Materials and Methods Thirteen AA and 15 Caucasian normal-weight adolescents (BMI <85th) underwent a 3-h hyperinsulinemic-euglycemic clamp, on two occasions in random order, after an overnight 12-hr infusion of: 1) 20% IL and 2) normal saline (NS). IMCL was quantified by 1H-magnetic resonance spectroscopy in tibialis anterior muscle before and after IL infusion. Results During IL infusion, plasma TG, glycerol, FFA and fat oxidation increased significantly, with no race differences. Hepatic insulin sensitivity decreased with IL infusion with no difference between the groups. IL infusion was associated with a significant increase in IMCL, which was comparable between AA (Δ 105%; NS: 1.9 ± 0.8 vs. IL: 3.9 ± 1.6 mmol/kg wet weight) and Caucasian (Δ 86%; NS: 2.8 ± 2.1 vs. IL: 5.2 ± 2.4 mmol/kg wet weight), with similar reductions (P<0.01) in insulin sensitivity between the groups (Δ −44%: NS: 9.1 ± 3.3 vs. IL: 5.1 ± 1.8 mg/kg/min per µU/ml in AA) and (Δ−39%: NS: 12.9 ± 6.0 vs. IL: 7.9 ± 3.8 mg/kg/min per µU/ml in Caucasian) adolescents. Conclusions In healthy adolescents, an acute elevation in plasma FFA with IL infusion is accompanied by significant increases in IMCL and reductions in insulin sensitivity with no race differential. Our findings suggest that AA normal-weight adolescents are not more susceptible than Caucasians to FFA-induced IMCL accumulation and insulin resistance. |
nfcorpus-qrel-MED-1491 | Generate text that best answers this question: saturated fat | Flaxseed fed pork: n-3 fatty acid enrichment and contribution to dietary recommendations.
The potential to increase n-3 fatty acid (FA) intake via flaxseed fed pork is underestimated when restricted to pure longissimus muscle, whereas a combination of muscle and adipose tissue is typically consumed. Presently, the FA content of pigs fed 0%, 5% and 10% dietary flaxseed for 11 weeks was measured in loin, picnic and butt primals (lean muscle with epimysium (L), L plus seam fat (LS), and LS plus 5 mm backfat (LSS)). The n-3 FA content necessary for an enrichment claim in Canada (300 mg/100 g serving) was exceeded in L from all primals when feeding 5% flaxseed, being 4 fold that of controls (P<0.001), with further enrichment from inclusion of associated adipose tissues (P<0.001). Increasing flaxseed feeding levels in combination with adipose tissue inclusion amplified total long chain n-3 FA (P<0.05), particularly 20:5n-3 and 22:5n-3. Flaxseed-fed n-3 FA enriched pork can contribute substantially to daily long chain n-3 FA intakes, particularly for societies with typically low seafood consumption. © 2013. |
nfcorpus-qrel-MED-1492 | Generate text that best answers this question: saturated fat | The effects of blood pressure reduction and of different blood pressure-lowering regimens on major cardiovascular events according to baseline bloo...
BACKGROUND: The benefits of reducing blood pressure are well established, but there remains uncertainty about whether the magnitude of the effect varies with the initial blood pressure level. The objective was to compare the risk reductions achieved by different blood pressure-lowering regimens among individuals with different baseline blood pressures. METHODS: Thirty-two randomized controlled trials were included and seven comparisons between different types of treatments were made. For each comparison, the primary prespecified analysis included calculation of summary estimates of effect using random-effects meta-analysis for major cardiovascular events in four groups defined by baseline SBP (<140, 140-159, 160-179, and ≥ 180 mmHg). RESULTS: There were 201 566 participants among whom 20 079 primary outcome events were observed. There was no evidence of differences in the proportionate risk reductions achieved with different blood pressure-lowering regimens across groups defined according to higher or lower levels of baseline SBP (all P for trend > 0.17). This finding was broadly consistent for comparisons of different regimens, for DBP categories, and for commonly used blood pressure cut-points. CONCLUSION: It appears unlikely that the effectiveness of blood pressure-lowering treatments depends substantively upon starting blood pressure level. As the majority of patients in the trials contributing to these overviews had a history of hypertension or were receiving background blood pressure-lowering therapy, the findings suggest that additional blood pressure reduction in hypertensive patients meeting initial blood pressure targets will produce further benefits. More broadly, the data are supportive of the utilization of blood pressure-lowering regimens in high-risk patients with and without hypertension. |
nfcorpus-qrel-MED-1493 | Generate text that best answers this question: saturated fat | Flaxseed - a miraculous defense against some critical maladies.
Presence of omega-3, omega-6 rich oil, alpha-linoleic acid, dietary fibers, secoisolariciresinol diglucoside, protein and minerals in flaxseed constitute a very strong basis for the utilization of flaxseed in various food preparations as a curative agent. An extensive body of literature illustrates that flaxseed has gained a significant position in the domain of nutritional sciences owing to its pivotal role as an antioxidant agent. The review discusses at length, numerous health benefits of flaxseed typically focusing its preventive role against cardiovascular diseases, cancer, diabetes and enhancement of spatial memory. Massive increase in the size of population with a special emphasize to the developing countries, there is an urge for exploration of the alternative dietary resources that can meet the dietary and nutritional needs of forthcoming generations. With respect to its remarkable nutritional importance, the review in question enables researchers engaged in nutritional sciences to further investigate the therapeutic value of flaxseed functional components and their dietary application in various food products and availability in processed foods as well as in the human cell line. |
nfcorpus-qrel-MED-1494 | Generate text that best answers this question: saturated fat | Potent antihypertensive action of dietary flaxseed in hypertensive patients.
Flaxseed contains ω-3 fatty acids, lignans, and fiber that together may provide benefits to patients with cardiovascular disease. Animal work identified that patients with peripheral artery disease may particularly benefit from dietary supplementation with flaxseed. Hypertension is commonly associated with peripheral artery disease. The purpose of the study was to examine the effects of daily ingestion of flaxseed on systolic (SBP) and diastolic blood pressure (DBP) in peripheral artery disease patients. In this prospective, double-blinded, placebo-controlled, randomized trial, patients (110 in total) ingested a variety of foods that contained 30 g of milled flaxseed or placebo each day over 6 months. Plasma levels of the ω-3 fatty acid α-linolenic acid and enterolignans increased 2- to 50-fold in the flaxseed-fed group but did not increase significantly in the placebo group. Patient body weights were not significantly different between the 2 groups at any time. SBP was ≈ 10 mm Hg lower, and DBP was ≈ 7 mm Hg lower in the flaxseed group compared with placebo after 6 months. Patients who entered the trial with a SBP ≥ 140 mm Hg at baseline obtained a significant reduction of 15 mm Hg in SBP and 7 mm Hg in DBP from flaxseed ingestion. The antihypertensive effect was achieved selectively in hypertensive patients. Circulating α-linolenic acid levels correlated with SBP and DBP, and lignan levels correlated with changes in DBP. In summary, flaxseed induced one of the most potent antihypertensive effects achieved by a dietary intervention. |
nfcorpus-qrel-MED-1495 | Generate text that best answers this question: saturated fat | Response surface methodology for predicting quality characteristics of beef patties added with flaxseed and tomato paste.
Response surface methodology was used to study the effect of flaxseed flour (FS) and tomato paste (TP) addition, from 0 to 10% and 0 to 20% respectively, on beef patty quality characteristics. The assessed quality characteristics were color (L, a, and b), pH and texture profile analysis (TPA). Also, sensory analysis was performed for the assessment of color, juiciness, firmness, and general acceptance. FS addition reduced L and a values and decreased weight loss of cooked products (P<0.05). An opposite effect was observed when TP was added (P<0.05). All TPA parameters decreased when percentages of FS and TP were increased in the formulation of beef patties. Furthermore, FS and TP addition adversely affected the sensory characteristics of the cooked product (P<0.05); nevertheless, all sensory characteristics evaluated had an acceptable score (>5.6). Thus FS and TP are ingredients that can be used in beef patty preparation. Copyright © 2014 Elsevier Ltd. All rights reserved. |
nfcorpus-qrel-MED-1496 | Generate text that best answers this question: saturated fat | Brain rust: recent discoveries on the role of oxidative stress in neurodegenerative diseases.
Oxidative stress (OS) and damages due to excessive reactive oxygen species (ROS) are common causes of injuries to cells and organisms. The prevalence of neurodegenerative diseases (ND) increases with aging and much of the research involving ROS and OS has emerged from works in this field. This text reviews some recent published articles about the role of OS in ND. Since there are many reviews in this field, the focus was centered in articles published recently. The Scientific Journals Directory supported by the Brazilian Ministry of Education Office for the Coordination of Higher Educational Personnel Improvement (CAPES) was used to search, download, and review articles. The search engine looked for the terms 'oxidative stress AND neurodegenerative diseases AND nutrition' in 10 different scientific collections. Biochemical markers for ND lack sensitivity or specificity for diagnosis or for tracking response to therapy today. OS has an intimate connection with ND, albeit low levels of ROS seem to protect the brain. Deleterious changes in mitochondria, OS, calcium, glucocorticoids, inflammation, trace metals, insulin, cell cycle, protein aggregation, and hundreds to thousands of genes occur in ND. The interaction of genes with their environment, may explain ND. Although OS has received much attention over the years, which increased the number of scientific works on antioxidant interventions, no one knows how to stop or delay ND at present. Interventions in vitro, in vivo, and in humans will continue to contribute for a better understanding of these pathologies. |
nfcorpus-qrel-MED-1497 | Generate text that best answers this question: saturated fat | Traumatic brain injury: a risk factor for Alzheimer's disease.
Traumatic brain injury (TBI) constitutes a major global health and socio-economic problem with neurobehavioral sequelae contributing to long-term disability. It causes brain swelling, axonal injury and hypoxia, disrupts blood brain barrier function and increases inflammatory responses, oxidative stress, neurodegeneration and leads to cognitive impairment. Epidemiological studies show that 30% of patients, who die of TBI, have Aβ plaques which are pathological features of Alzheimer's disease (AD). Thus TBI acts as an important epigenetic risk factor for AD. This review focuses on AD related genes which are expressed during TBI and its relevance to progression of the disease. Such understanding will help to diagnose the risk of TBI patients to develop AD and design therapeutic interventions. Copyright © 2012 Elsevier Ltd. All rights reserved. |
nfcorpus-qrel-MED-1498 | Generate text that best answers this question: saturated fat | A modest proposal for a longitudinal study of dementia prevention (with apologies to Jonathan Swift, 1729).
Many studies have documented the role of risk and protective factors for late life dementing illnesses, particularly Alzheimer's disease. A "Systematic Review" from the US Agency for Healthcare Research and Quality and the National Institute on Aging concluded that because the overall quality of evidence was low, recommendations for public health could not be made. In order to gain evidence for the efficacy of lifestyle interventions, we propose a "Modest Proposal" to study 10,000 subjects over 40 years randomly assigned to groups of low or high saturated fat in the diet, head injury, and high or low levels of mental activity, physical activity, or inactivity as well as smoking or non-smoking. This proposed study cannot be accomplished. The "Modest Proposal" illustrates that the absence of definitive evidence should not restrict physicians from making reasonable recommendations based on the evidence that is available. |
nfcorpus-qrel-MED-1499 | Generate text that best answers this question: saturated fat | Neuroprotective effect of natural products against Alzheimer's disease.
Nature has gifted mankind with a plethora of flora-bearing fruits, vegetables and nuts. The diverse array of bioactive nutrients present in these natural products plays a pivotal role in prevention and cure of various neurodegenerative diseases, such as Alzheimer's disease (AD), Parkinson's disease and other neuronal dysfunctions. Accumulated evidence suggests that naturally occurring phyto-compounds, such as polyphenolic antioxidants found in fruits, vegetables, herbs and nuts, may potentially hinder neurodegeneration, and improve memory and cognitive function. Nuts such as walnut have also demonstrated neuroprotective effect against AD. The molecular mechanisms behind the curative effects rely mainly on the action of phytonutrients on distinct signalling pathways associated with protein folding and neuroinflammation. The neuroprotective effects of various naturally occurring compounds in AD is evaluating in this review. |
nfcorpus-qrel-MED-1500 | Generate text that best answers this question: saturated fat | Fruit, vegetables and prevention of cognitive decline or dementia: a systematic review of cohort studies.
BACKGROUND: Regular consumption of fruit and vegetables has been considered to be associated with a reduced risk of dementia and age-associated cognitive decline, although the association is currently unsupported by a systematic review of the literature. METHODS: We searched Medline, Embase, Biosis, ALOIS, the Cochrane library, different publisher databases as well as bibliographies of retrieved articles. All cohort studies with a follow-up of 6 months or longer were included if they reported an association of Alzheimer's disease or cognitive decline in regard to the frequency of fruit and vegetables consumption. FINDINGS: Nine studies with a total of 44,004 participants met the inclusion criteria. Six studies analyzed fruit and vegetables separately and five of them found that higher consumption of vegetables, but not fruit is associated with a decreased risk of dementia or cognitive decline. The same association was found by three further studies for fruit and vegetable consumption analytically combined. CONCLUSION: Increased intake of vegetables is associated with a lower risk of dementia and slower rates of cognitive decline in older age. Yet, evidence that this association is also valid for high fruit consumption is lacking. |
nfcorpus-qrel-MED-1501 | Generate text that best answers this question: saturated fat | Systematic review: factors associated with risk for and possible prevention of cognitive decline in later life.
BACKGROUND: Many biological, behavioral, social, and environmental factors may contribute to the delay or prevention of cognitive decline. PURPOSE: To summarize evidence about putative risk and protective factors for cognitive decline in older adults and the effects of interventions for preserving cognition. DATA SOURCES: English-language publications in MEDLINE, HuGEpedia, AlzGene, and the Cochrane Database of Systematic Reviews from 1984 through 27 October 2009. STUDY SELECTION: Observational studies with 300 or more participants and randomized, controlled trials (RCTs) with 50 or more adult participants who were 50 years or older, drawn from general populations, and followed for at least 1 year were included. Relevant, good-quality systematic reviews were also eligible. DATA EXTRACTION: Information on study design, outcomes, and quality were extracted by one researcher and verified by another. An overall rating of the quality of evidence was assigned by using the GRADE (Grading of Recommendations Assessment, Development, and Evaluation) criteria. DATA SYNTHESIS: 127 observational studies, 22 RCTs, and 16 systematic reviews were reviewed in the areas of nutritional factors; medical factors and medications; social, economic, or behavioral factors; toxic environmental exposures; and genetics. Few of the factors had sufficient evidence to support an association with cognitive decline. On the basis of observational studies, evidence that supported the benefits of selected nutritional factors or cognitive, physical, or other leisure activities was limited. Current tobacco use, the apolipoprotein E epsilon4 genotype, and certain medical conditions were associated with increased risk. One RCT found a small, sustained benefit from cognitive training (high quality of evidence) and a small RCT reported that physical exercise helps to maintain cognitive function. LIMITATIONS: The categorization and definition of exposures were heterogeneous. Few studies were designed a priori to assess associations between specific exposures and cognitive decline. The review included only English-language studies, prioritized categorical outcomes, and excluded small studies. CONCLUSION: Few potentially beneficial factors were identified from the evidence on risk or protective factors associated with cognitive decline, but the overall quality of the evidence was low. PRIMARY FUNDING SOURCE: Agency for Healthcare Research and Quality and the National Institute on Aging, through the Office of Medical Applications of Research, National Institutes of Health. |
nfcorpus-qrel-MED-1502 | Generate text that best answers this question: saturated fat | The longer-term impacts of Western diet on human cognition and the brain.
Animal work over the last three decades has generated a convincing body of evidence that a Western diet - one high in saturated fat and refined carbohydrates (HFS diet) - can damage various brain systems. In this review we examine whether there is evidence for this in humans, using converging lines of evidence from neuropsychological, epidemiological and neuroimaging data. Using the animal research as the organizing principal, we examined evidence for dietary induced impairments in frontal, limbic and hippocampal systems, and with their associated functions in learning, memory, cognition and hedonics. Evidence for the role of HFS diet in attention deficit disorder and in neurodegenerative conditions was also examined. While human research data is still at an early stage, there is evidence of an association between HFS diet and impaired cognitive function. Based upon the animal data, and a growing understanding of how HFS diets can disrupt brain function, we further suggest that there is a causal link running from HFS diet to impaired brain function in humans, and that HFS diets also contribute to the development of neurodegenerative conditions. Crown Copyright © 2013. Published by Elsevier Ltd. All rights reserved. |
nfcorpus-qrel-MED-1503 | Generate text that best answers this question: saturated fat | A possible role for lutein and zeaxanthin in cognitive function in the elderly.
Epidemiologic studies suggest that dietary lutein and zeaxanthin may be of benefit in maintaining cognitive health. Among the carotenoids, lutein and zeaxanthin are the only two that cross the blood-retina barrier to form macular pigment (MP) in the eye. They also preferentially accumulate in the human brain. Lutein and zeaxanthin in macula from nonhuman primates were found to be significantly correlated with their concentrations in matched brain tissue. Therefore, MP can be used as a biomarker of lutein and zeaxanthin in primate brain tissue. This is of interest given that a significant correlation was found between MP density and global cognitive function in healthy older adults. An examination of a relation between cognition and lutein and zeaxanthin concentrations in the brain tissue of decedents from a population-based study in centenarians found that zeaxanthin concentrations in brain tissue were significantly related to antemortem measures of global cognitive function, memory retention, verbal fluency, and dementia severity after adjustment for age, sex, education, hypertension, and diabetes. In univariate analyses, lutein was related to recall and verbal fluency, but the strength of the associations was attenuated with adjustment for covariates. However, lutein concentrations in the brain were significantly lower in individuals with mild cognitive impairment than in those with normal cognitive function. Last, in a 4-mo, double-blinded, placebo-controlled trial in older women that involved lutein supplementation (12 mg/d), alone or in combination with DHA (800 mg/d), verbal fluency scores improved significantly in the DHA, lutein, and combined-treatment groups. Memory scores and rate of learning improved significantly in the combined-treatment group, who also showed a trend toward more efficient learning. When all of these observations are taken into consideration, the idea that lutein and zeaxanthin can influence cognitive function in older adults warrants further study. |
nfcorpus-qrel-MED-1504 | Generate text that best answers this question: saturated fat | Risk factors and preventive interventions for Alzheimer disease: state of the science.
BACKGROUND: Numerous studies have investigated risk factors for Alzheimer disease (AD). However, at a recent National Institutes of Health State-of-the-Science Conference, an independent panel found insufficient evidence to support the association of any modifiable factor with risk of cognitive decline or AD. OBJECTIVE: To present key findings for selected factors and AD risk that led the panel to their conclusion. DATA SOURCES: An evidence report was commissioned by the Agency for Healthcare Research and Quality. It included English-language publications in MEDLINE and the Cochrane Database of Systematic Reviews from 1984 through October 27, 2009. Expert presentations and public discussions were considered. STUDY SELECTION: Study inclusion criteria for the evidence report were participants aged 50 years and older from general populations in developed countries; minimum sample sizes of 300 for cohort studies and 50 for randomized controlled trials; at least 2 years between exposure and outcome assessment; and use of well-accepted diagnostic criteria for AD. DATA EXTRACTION: Included studies were evaluated for eligibility and data were abstracted. Quality of overall evidence for each factor was summarized as low, moderate, or high. DATA SYNTHESIS: Diabetes mellitus, hyperlipidemia in midlife, and current tobacco use were associated with increased risk of AD, and Mediterranean-type diet, folic acid intake, low or moderate alcohol intake, cognitive activities, and physical activity were associated with decreased risk. The quality of evidence was low for all of these associations. CONCLUSION: Currently, insufficient evidence exists to draw firm conclusions on the association of any modifiable factors with risk of AD. |
nfcorpus-qrel-MED-1505 | Generate text that best answers this question: saturated fat | Nutritional modulation of cognitive function and mental health.
The important role of diet in cardiometabolic health is generally well recognised; for mental health, it is not so well understood. However, lifestyle risk factors for poor physical health are the same risk factors for mental illness, including poor diet. This is reflected by the high level of poor physical health in people with mental illness. Mediterranean, whole food diets have been associated with reduced risk for chronic disease, but very little research has investigated their mental health benefits. We provide a model for the pathways by which food components provided by a Mediterranean-style diet can facilitate healthy brain function. We then review evidence for the role of selected nutrients/food components - antioxidants, omega-3 fatty acids and B vitamins - in the brain and, hence, modulation of cognitive function and mental health. Converging evidence indicates multiple pathways by which these nutrients can assist in brain function, drawing from studies investigating them in isolation. There is very little work done on synergistic actions of nutrients and whole diets, highlighting a need for human intervention studies investigating benefits of Mediterranean-style diets for mental, as well as cardiometabolic health. Copyright © 2013 Elsevier Inc. All rights reserved. |
nfcorpus-qrel-MED-1506 | Generate text that best answers this question: saturated fat | Western Diet Consumption and Cognitive Impairment: Links to Hippocampal Dysfunction and Obesity
Intake of saturated fats and simple carbohydrates, two of the primary components of a modern Western diet, is linked with the development of obesity and Alzheimer's Disease. The present paper summarizes research showing that Western diet intake is associated with cognitive impairment, with a specific emphasis on learning and memory functions that are dependent on the integrity of the hippocampus. The paper then considers evidence that saturated fat and simple carbohydrate intake is correlated with neurobiological changes in the hippocampus that may be related to the ability of these dietary components to impair cognitive function. Finally, a model is described proposing that Western diet consumption contributes to the development of excessive food intake and obesity, in part, by interfering with a type of hippocampal-dependent memory inhibition that is critical in the ability of animals to refrain from responding to environmental cues associated with food, and ultimately from consuming energy intake in excess of that driven solely by caloric need. |
nfcorpus-qrel-MED-1551 | Generate text that best answers this question: saturated fat | Effect of ingestion of meat on plasma cholesterol of vegetarians.
In a controlled trial, 21 strict vegetarians were studied prospectively for eight weeks: a two-week control period of the usual vegetarian diet was followed by four weeks, during which 250 g of beef was added isocalorically to the daily vegetarian diet and then by two weeks of the control diet. Plasma high-density lipoprotein-cholesterol did not change during the study, whereas plasma total cholesterol rose significantly by 19% at the end of the meat-eating period. Systolic blood pressure (BP) increased significantly during the meat eating by 3% over control values, whereas diastolic BP showed no major changes. Plasma renin activity, prostaglandin A and E levels, and urinary kallikrein, norepinephrine, and epinephrine excretions were within normal limits and did not change notably throughout the trial. The study suggests an adverse effect of consumption of beef on plasma lipid and BP levels. |
nfcorpus-qrel-MED-1552 | Generate text that best answers this question: saturated fat | Dietary lipids and blood cholesterol: quantitative meta-analysis of metabolic ward studies.
OBJECTIVE: To determine the quantitative importance of dietary fatty acids and dietary cholesterol to blood concentrations of total, low density lipoprotein, and high density lipoprotein cholesterol. DESIGN: Meta-analysis of metabolic ward studies of solid food diets in healthy volunteers. SUBJECTS: 395 dietary experiments (median duration 1 month) among 129 groups of individuals. RESULTS: Isocaloric replacement of saturated fats by complex carbohydrates for 10% of dietary calories resulted in blood total cholesterol falling by 0.52 (SE 0.03) mmol/l and low density lipoprotein cholesterol falling by 0.36 (0.05) mmol/l. Isocaloric replacement of complex carbohydrates by polyunsaturated fats for 5% of dietary calories resulted in total cholesterol falling by a further 0.13 (0.02) mmol/l and low density lipoprotein cholesterol falling by 0.11 (0.02) mmol/l. Similar replacement of carbohydrates by monounsaturated fats produced no significant effect on total or low density lipoprotein cholesterol. Avoiding 200 mg/day dietary cholesterol further decreased blood total cholesterol by 0.13 (0.02) mmol/l and low density lipoprotein cholesterol by 0.10 (0.02) mmol/l. CONCLUSIONS: In typical British diets replacing 60% of saturated fats by other fats and avoiding 60% of dietary cholesterol would reduce blood total cholesterol by about 0.8 mmol/l (that is, by 10-15%), with four fifths of this reduction being in low density lipoprotein cholesterol. |
nfcorpus-qrel-MED-1553 | Generate text that best answers this question: saturated fat | Developing actionable dietary guidance messages: dietary fat as a case study.
Although consumers say they are concerned about nutrition and are aware that eating a healthful diet is important for good health, this knowledge does not always translate into healthful diet behaviors or motivate behavior change. In an effort to better understand consumer attitudes about nutrition and to explore alternatives for communicating dietary advice in language that is meaningful and motivates behavior change, the International Food Information Council (IFIC) conducted qualitative research with consumers (using focus groups) and registered dietitians (using telephone interviews) in 1998 and 1999. Results of the research are presented using dietary fat as a case study. Findings from the IFIC research were reported to the Dietary Guidelines Advisory Committee to assist the Committee in developing meaningful and action-oriented dietary advice related to dietary fat for inclusion in the 2000 Dietary Guidelines for Americans that would be motivating and easy for consumers to implement. The recommendation to moderate fat intake in the new dietary guideline, "Choose a diet that is low in saturated fat and cholesterol and moderate in total fat" is consistent with communication recommendations in the IFIC research. Further, the moderate fat message is empowering because it suggests an achievable dietary regimen and reduces guilt and worry about foods. It allows flexibility to enjoy desired foods and promotes using common sense when it comes to diet. Several issues emerged from the IFIC research that apply to general nutrition communications with consumers, whether it be through national nutrition recommendations or in one-on-one counseling situations: to be effective, messages to consumers about nutrition, and specifically dietary fat, must address sources of discomfort about dietary choices; they must engender a sense of empowerment; and they should motivate both by providing clear information that propels toward taking action and appeals to the need to make personal choices. |
nfcorpus-qrel-MED-1554 | Generate text that best answers this question: saturated fat | Reduced or modified dietary fat for preventing cardiovascular disease.
BACKGROUND: Reduction or modification of dietary fat can improve total cholesterol levels, but may also have a variety of effects, both positive and negative, on other cardiovascular risk factors. OBJECTIVES: The aim of this systematic review was to assess the effect of reduction or modification of dietary fats on total and cardiovascular mortality and cardiovascular morbidity over at least 6 months, using all available randomized clinical trials. SEARCH STRATEGY: The Cochrane Library, MEDLINE, EMBASE, CAB s, CVRCT registry and related Cochrane Groups' trial registers were searched through spring 1998, SIGLE to January 1999. Trials known to experts in the field and biographies were included through May 1999. SELECTION CRITERIA: Trials fulfilled the following criteria: 1) randomized with appropriate control group, 2) intention to reduce or modify fat or cholesterol intake (excluding exclusively omega-3 fat interventions), 3) not multi factorial, 4) healthy adult humans, 5) intervention at least six months, 6) mortality or cardiovascular morbidity data available. Inclusion decisions were duplicated, disagreement resolved by discussion or a third party. DATA COLLECTION AND ANALYSIS: Rate data were extracted by two independent reviewers and meta-analysis performed using random effects methodology. Meta-regression and funnel plots were used. MAIN RESULTS: Twenty seven studies were included (40 intervention arms, 30,901 person-years). There was no significant effect on total mortality (rate ratio 0.98, 95% CI 0.86 to 1.12), a trend towards protection form cardiovascular mortality (rate ratio 0.91, 95% CI 0.77 to 1.07), and significant protection from cardiovascular events (rate ratio 0.84, 95% CI 0.72 to 0.99). The latter became non-significant on sensitivity analysis. Trials where participants were involved for more than 2 years showed significant reductions in the rate of cardiovascular events and a suggestion of protection from total mortality. The degree of protection from cardiovascular events appeared similar in high and low risk groups, but was statistically significant only in the former. REVIEWER'S CONCLUSIONS: The findings are suggestive of a small but potentially important reduction in cardiovascular risk in trials longer than two years. Lifestyle advice to all those at high risk of cardiovascular disease (especially where statins are unavailable or rationed), and to lower risk population groups, should continue to include permanent reduction of dietary saturated fat and partial replacement by unsaturates. |
nfcorpus-qrel-MED-1555 | Generate text that best answers this question: saturated fat | Diet and serum cholesterol: do zero correlations negate the relationship?
The confounding that results from the uncontrolled conditions under which most epidemiologic observations are made is sufficient to undermine their validity with respect to investigation of the relationship between diet and serum cholesterol. In this paper, the authors show, using both a mathematical model and referring to empirical data, that if certain variances are sufficiently great, even when there is cause and effect, correlation coefficients close to zero would be expected from the actual data of a cross-sectional study. Cross-sectional designs are therefore not suitable for studying this relationship. |
nfcorpus-qrel-MED-1556 | Generate text that best answers this question: saturated fat | Meta-analysis of prospective cohort studies evaluating the association of saturated fat with cardiovascular disease
Background: A reduction in dietary saturated fat has generally been thought to improve cardiovascular health. Objective: The objective of this meta-analysis was to summarize the evidence related to the association of dietary saturated fat with risk of coronary heart disease (CHD), stroke, and cardiovascular disease (CVD; CHD inclusive of stroke) in prospective epidemiologic studies. Design: Twenty-one studies identified by searching MEDLINE and EMBASE databases and secondary referencing qualified for inclusion in this study. A random-effects model was used to derive composite relative risk estimates for CHD, stroke, and CVD. Results: During 5–23 y of follow-up of 347,747 subjects, 11,006 developed CHD or stroke. Intake of saturated fat was not associated with an increased risk of CHD, stroke, or CVD. The pooled relative risk estimates that compared extreme quantiles of saturated fat intake were 1.07 (95% CI: 0.96, 1.19; P = 0.22) for CHD, 0.81 (95% CI: 0.62, 1.05; P = 0.11) for stroke, and 1.00 (95% CI: 0.89, 1.11; P = 0.95) for CVD. Consideration of age, sex, and study quality did not change the results. Conclusions: A meta-analysis of prospective epidemiologic studies showed that there is no significant evidence for concluding that dietary saturated fat is associated with an increased risk of CHD or CVD. More data are needed to elucidate whether CVD risks are likely to be influenced by the specific nutrients used to replace saturated fat. |
nfcorpus-qrel-MED-1557 | Generate text that best answers this question: saturated fat | Intake of fatty acids in general populations worldwide does not meet dietary recommendations to prevent coronary heart disease: a systematic review...
AIM: To systematically review data from different countries on population intakes of total fat, saturated fatty acids (SFA) and polyunsaturated fatty acids (PUFA), and to compare these to recommendations from the Food and Agriculture Organization of the United Nations/the World Health Organization (FAO/WHO). METHODS: Data from national dietary surveys or population studies published from 1995 were searched via MEDLINE, Web of Science and websites of national public health institutes. RESULTS: Fatty acid intake data from 40 countries were included. Total fat intake ranged from 11.1 to 46.2 percent of energy intake (% E), SFA from 2.9 to 20.9% E and PUFA from 2.8 to 11.3% E. The mean intakes met the recommendation for total fat (20-35% E), SFA (<10% E) and PUFA (6-11% E) in 25, 11 and 20 countries, respectively. SFA intake correlated with total fat intake (r = 0.76, p < 0.01) but not with PUFA intake (r = 0.03, p = 0.84). Twenty-seven countries provided data on the distribution of fatty acids intake. In 18 of 27 countries, more than 50% of the population had SFA intakes >10% E and in 13 of 27 countries, the majority of the population had PUFA intakes <6% E. CONCLUSIONS: In many countries, the fatty acids intake of adults does not meet the levels that are recommended to prevent chronic diseases. The relation between SFA and PUFA intakes shows that lower intakes of SFA in the populations are not accompanied by higher intakes of PUFA, as is recommended for preventing coronary heart disease. |
nfcorpus-qrel-MED-1558 | Generate text that best answers this question: saturated fat | Recommended dietary reference intakes, nutritional goals and dietary guidelines for fat and fatty acids: a systematic review.
Dietary fat and its effects on health and disease has attracted interest for research and Public Health. Since the 1980s many bodies and organizations have published recommendations regarding fat intake. In this paper different sets of recommendations are analyzed following a systematic review process to examine dietary reference intakes, nutritional goals and dietary guidelines for fat and fatty acids. A literature search was conducted in relevant literature databases along a search for suitable grey literature reports. Documents were included if they reported information on either recommended intake levels or dietary reference values or nutritional objectives or dietary guidelines regarding fat and/or fatty acids and/or cholesterol intake or if reported background information on the process followed to produce the recommendations. There is no standard approach for deriving nutrient recommendations. Recommendations vary between countries regarding the levels of intake advised, the process followed to set the recommendations. Recommendations on fat intake share similar figures regarding total fat intake, saturated fats and trans fats. Many sets do not include a recommendation about cholesterol intake. Most recent documents provide advice regarding specific n-3 fatty acids. Despite efforts to develop evidence based nutrient recommendations and dietary guidelines that may contribute to enhance health, there are still many gaps in research. It would be desirable that all bodies concerned remain transparent about the development of dietary recommendations. In order to achieve this, the type of evidence selected to base the recommendations should be specified and ranked. Regular updates of such recommendations should be planned. |
nfcorpus-qrel-MED-1762 | Generate text that best answers this question: saturated fat | Meat intake and reproductive parameters among young men
Background In the United States, anabolic sex steroids are administered to cattle for growth promotion. There is concern regarding the reproductive consequences of this practice for men who eat beef. We investigated whether meat consumption was associated with semen quality parameters and reproductive hormone levels in young men. Methods Semen samples were obtained from 189 men aged 18-22 years. Diet was assessed with a previously validated food frequency questionnaire. We used linear regression to analyze the cross-sectional associations of meat intake with semen quality parameters and reproductive hormones, while adjusting for potential confounders. Results There was an inverse relation between processed red meat intake and total sperm count. The adjusted relative differences in total sperm counts for men in increasing quartiles of processed meat intake were 0 (ref), −3 (95% confidence interval = −67 to 37), −14 (−82 to 28), and −78 (−202 to −5) million (test for trend, P = 0.01). This association was strongest among men with abstinence time less than 2 days and was driven by a strong inverse relation between processed red meat intake and ejaculate volume (test for trend, P =0.003). Conclusions In our population of young men, processed meat intake was associated with lower total sperm count. We cannot distinguish whether this association is due to residual confounding by abstinence time or represents a true biological effect. |
nfcorpus-qrel-MED-1763 | Generate text that best answers this question: saturated fat | The sensitivity of the child to sex steroids: possible impact of exogenous estrogens.
The current trends of increasing incidences of testis, breast and prostate cancers are poorly understood, although it is assumed that sex hormones play a role. Disrupted sex hormone action is also believed to be involved in the increased occurrence of genital abnormalities among newborn boys and precocious puberty in girls. In this article, recent literature on sex steroid levels and their physiological roles during childhood is reviewed. It is concluded that (i) circulating levels of estradiol in prepubertal children are lower than originally claimed; (ii) children are extremely sensitive to estradiol and may respond with increased growth and/or breast development even at serum levels below the current detection limits; (iii) no threshold has been established, below which no hormonal effects can be seen in children exposed to exogenous steroids or endocrine disruptors; (iv) changes in hormone levels during fetal and prepubertal development may have severe effects in adult life and (v) the daily production rates of sex steroids in children estimated by the Food and Drug Administration in 1999 and still used in risk assessments are highly overestimated and should be revised. Because no lower threshold for estrogenic action has been established, caution should be taken to avoid unnecessary exposure of fetuses and children to exogenous sex steroids and endocrine disruptors, even at very low levels. |
nfcorpus-qrel-MED-1764 | Generate text that best answers this question: saturated fat | Lipid Concentrations and Semen Quality: The LIFE Study
The decline in sperm count rates over the last 50 years appears to parallel the rising prevalence of obesity. As lipids levels are strongly associated with obesity, high lipids levels or hyperlipidemia may thus play an important role in the decline in fertility in addition to other environmental or lifestyle factors. The objective of this population based cohort study was to evaluate the association between men’s serum lipid concentrations and semen quality parameters among 501 male partners of couples desiring pregnancy and discontinuing contraception. Each participant provided prospectively up to two semen samples (94% of men provided one or more semen samples, and 77% of men provided a second sample approximately one month later). Linear mixed effects models were used to estimate the associations between baseline lipid concentrations and semen quality parameters, adjusted for age, body mass index, and race. We found that higher levels of serum total cholesterol, free cholesterol and phospholipids were associated with a significantly lower percentage of sperm with intact acrosome and smaller sperm head area and perimeter. Our results suggest that lipid concentrations may affect semen parameters, specifically sperm head morphology, highlighting the importance of cholesterol and lipid homeostasis for male fecundity. |
nfcorpus-qrel-MED-1765 | Generate text that best answers this question: saturated fat | Effects of simvastatin and pravastatin on gonadal function in male hypercholesterolemic patients.
Inhibition of cholesterol biosynthesis by hydroxymethyl glutaryl coenzyme A (HMG-CoA) reductase inhibitors could, in theory, adversely affect male gonadal function because cholesterol is a precursor of steroid hormones. The objective of this randomized double-blind trial was to compare the effects of simvastatin, pravastatin, and placebo on gonadal testosterone production and spermatogenesis. After a 6-week placebo and lipid-lowering diet run-in period, 159 male patients aged 21 to 55 years with type IIa or IIb hypercholesterolemia, low-density lipoprotein (LDL) cholesterol between 145 and 240 mg/dL, and normal basal levels of testosterone were randomly assigned to treatment with simvastatin 20 mg (n = 40), simvastatin 40 mg (n = 41), pravastatin 40 mg (n = 39), or placebo (n = 39) once daily. After 24 weeks of treatment, mean total cholesterol levels were decreased 24% to 27% and mean LDL cholesterol was decreased 30% to 34% in the 3 active-treatment groups (P < .001 for all comparisons to placebo). At 24 weeks, there were no statistically significant differences between the placebo group and any of the active-treatment groups for the change from baseline in testosterone, human chorionic gonadotropin (hCG)stimulated testosterone, free testosterone index, follicle-stimulating hormone (FSH), luteinizing hormone (LH), or sex hormone-binding globulin (SHBG). Moreover, there were no statistically significant differences at week 12 or week 24 for the change from baseline in sperm concentration, ejaculate volume, or sperm motility for any active treatment relative to placebo. Both simvastatin and pravastatin were well tolerated. In summary, we found no evidence for clinically meaningful effects of simvastatin or pravastatin on gonadal testosterone production, testosterone reserve, or multiple parameters of semen quality. |
nfcorpus-qrel-MED-1766 | Generate text that best answers this question: saturated fat | Lipids and testicular function.
We studied 19 male patients with primary hyperlipoproteinaemia, a control group of 28 healthy men and 44 infertile males before any treatment was undertaken. Spermiogram, seminal biochemical studies, measurements of plasma hormone levels and lipid determinations were carried out. Most hyperlipoproteinaemic patients showed abnormalities in the spermiograms and the mean values were lower than in the controls except for semen volume. Seminal biochemical determinations were normal in the majority and the hormone profile showed some abnormal values, mainly for E2. Lipid abnormalities were more common in azoospermic infertile men and mean lipid levels were higher. Correlation studies suggest that high levels of C and/or Tg are associated with poor semen quality and higher FSH levels. The results of our studies suggest that high lipid levels exert adverse direct effects at the testicular level. |
nfcorpus-qrel-MED-1778 | Generate text that best answers this question: saturated fat | Dairy intake and semen quality among men attending a fertility clinic
Objective To examine the relationship between dairy food intake and semen parameters Design Longitudinal study Setting Men attending academic medical center fertility clinic in Boston, MA Patients 155 men Interventions None Main Outcome Measures total sperm count, sperm concentration, progressive motility, and morphology Results Low-fat dairy intake was positively related to sperm concentration and progressive motility. On average, men in the highest quartile of intake (1.22–3.54 servings/day) had 33% (95% confidence interval (CI) 1, 55) higher sperm concentration and 9.3 (95%CI 1.4, 17.2) percentage units higher sperm motility than men in the lowest quartile of intake (≤0.28 servings/day). These associations were primarily explained by intake of low-fat milk. The corresponding results for low-fat milk were 30% (95%CI 1,51) higher sperm concentration and 8.7 (95%CI 3.0, 14.4) percentage units higher sperm motility. Cheese intake was associated with lower sperm concentration among ever smokers. In this group, men in the highest tertile of intake (0.82–2.43 servings/day) had 53.2% (95%CI 9.7, 75.7) lower sperm concentration than men in the lowest tertile of cheese intake (<0.43 servings/day). Conclusions Our findings suggest that low-fat dairy intake, particularly low-fat milk, is related to higher sperm concentration and progressive motility, while cheese intake to lower sperm concentration among past or current smokers. |
nfcorpus-qrel-MED-1768 | Generate text that best answers this question: saturated fat | Is milk responsible for male reproductive disorders?
The role of environmental compounds with estrogenic activity in the development of male reproductive disorders has been a source of great concern. Among the routes of human exposure to estrogens, we are particularly concerned about cows' milk, which contains considerable amounts of estrogens. The major sources of animal-derived estrogens in the human diet are milk and dairy products, which account for 60-70% of the estrogens consumed. Humans consume milk obtained from heifers in the latter half of pregnancy, when the estrogen levels in cows are markedly elevated. The milk that we now consume may be quite unlike that consumed 100 years ago. Modern genetically-improved dairy cows, such as the Holstein, are usually fed a combination of grass and concentrates (grain/protein mixes and various by-products), allowing them to lactate during the latter half of pregnancy, even at 220 days of gestation. We hypothesize that milk is responsible, at least in part, for some male reproductive disorders. Copyright 2001 Harcourt Publishers Ltd. |
nfcorpus-qrel-MED-4951 | Generate text that best answers this question: saturated fat | Role of environmental estrogens in the deterioration of male factor fertility.
OBJECTIVE: To evaluate the role of the environmental estrogens polychlorinated biphenyls (PCBs) and phthalate esters (PEs) as potential environmental hazards in the deterioration of semen parameters in infertile men without an obvious etiology. DESIGN: Randomized controlled study. SETTING: Tertiary care referral infertility clinic and academic research center. PATIENT(S): Twenty-one infertile men with sperm counts <20 million/mL and/or rapid progressive motility <25% and/or <30% normal forms without evidence of an obvious etiology and 32 control men with normal semen analyses and evidence of conception. Semen and blood samples were obtained as part of the treatment protocol. MAIN OUTCOME MEASURE(S): Evaluation of semen parameters such as ejaculate volume, sperm count, motility, morphology, vitality, osmoregulatory capacity, sperm chromatin stability, and sperm nuclear DNA integrity. RESULT(S): PCBs were detected in the seminal plasma of infertile men but not in controls, and the concentration of PEs was significantly higher in infertile men compared with controls. Ejaculate volume, sperm count, progressive motility, normal morphology, and fertilizing capacity were significantly lower in infertile men compared with controls. The highest average PCB and PE concentrations were found in urban fish eaters, followed by rural fish eaters, urban vegetarians, and rural vegetarians. The total motile sperm counts in infertile men were inversely proportional to their xenoestrogen concentrations and were significantly lower than those in the respective controls. CONCLUSION(S): PCBs and PEs may be instrumental in the deterioration of semen quality in infertile men without an obvious etiology. |
nfcorpus-qrel-MED-1770 | Generate text that best answers this question: saturated fat | Possible health impact of animal oestrogens in food.
Oestrogens govern reproductive functions in vertebrates, and are present in all animal tissues. The theoretical maximum daily intake (TMDI) of oestradiol-17beta by consumption of cattle meat is calculated to be 4.3 ng. Following the use of oestradiol-containing growth-promoting agents, TMDI is increased by a factor of 4.6 to 20 ng oestradiol-17beta, assuming that single dosage and 'good animal husbandry' are observed. Pork and poultry probably contain similar amounts of oestrogens as untreated cattle. The mean concentration of oestradiol-17beta in whole milk is estimated at 6.4 pg/ml. Scarce data available on eggs report up to 200 pg/g oestradiol-17beta. The risk evaluation of oestrogenic growth-promoting agents is limited by analytical uncertainties. Residues of oestradiol-17alpha and the importance of oestrogen conjugates are widely unknown. The performance of mass spectrometry still needs to be improved for confirmation of oestrogen concentrations in most food. At present, the potential relevance of oestradiol acyl esters, the actual daily production rate of oestradiol in prepubertal children, and the role of oestradiol metabolites in cancer are obscure. The presence of different cytoplasmic oestrogen receptor subtypes and potential oestradiol effects in non-reproductive functions require further examination. |
nfcorpus-qrel-MED-1771 | Generate text that best answers this question: saturated fat | Some observations on human semen analysis.
Semen analysis of 66 unmarried medical students in the age group of 17-21 years was carried out. A higher liquefaction time pH, motility, lower sperm count and abnormal forms were observed compared to reported values. Liquefaction time, pH and sperm count was found significantly different in non-vegetarians and vegetarians, perhaps due to difference in their dietary proteins. |
nfcorpus-qrel-MED-1781 | Generate text that best answers this question: saturated fat | High dietary intake of saturated fat is associated with reduced semen quality among 701 young Danish men from the general population.
BACKGROUND: Saturated fat intake has been associated with both cardiovascular disease and cancer risk, and a newly published study found an association between saturated fat intake and a lower sperm concentration in infertile men. OBJECTIVE: The objective was to examine the association between dietary fat intake and semen quality among 701 young Danish men from the general population. DESIGN: In this cross-sectional study, men were recruited when they were examined to determine their fitness for military service from 2008 to 2010. They delivered a semen sample, underwent a physical examination, and answered a questionnaire comprising a quantitative food-frequency questionnaire to assess food and nutrient intakes. Multiple linear regression analyses were performed with semen variables as outcomes and dietary fat intakes as exposure variables, adjusted for confounders. RESULTS: A lower sperm concentration and total sperm count in men with a high intake of saturated fat was found. A significant dose-response association was found, and men in the highest quartile of saturated fat intake had a 38% (95% CI: 0.1%, 61%) lower sperm concentration and a 41% (95% CI: 4%, 64%) lower total sperm count than did men in the lowest quartile. No association between semen quality and intake of other types of fat was found. CONCLUSIONS: Our findings are of potentially great public interest, because changes in diet over the past decades may be part of the explanation for the recently reported high frequency of subnormal human sperm counts. A reduction in saturated fat intake may be beneficial for both general and reproductive health. |
nfcorpus-qrel-MED-1773 | Generate text that best answers this question: saturated fat | Dairy food intake in relation to semen quality and reproductive hormone levels among physically active young men
STUDY QUESTION Is increased consumption of dairy foods associated with lower semen quality? SUMMARY ANSWER We found that intake of full-fat dairy was inversely related to sperm motility and morphology. These associations were driven primarily by intake of cheese and were independent of overall dietary patterns. WHAT IS KNOWN ALREADY It has been suggested that environmental estrogens could be responsible for the putative secular decline in sperm counts. Dairy foods contain large amounts of estrogens. While some studies have suggested dairy as a possible contributing factor for decreased semen quality, this finding has not been consistent across studies. STUDY DESIGN, SIZE, DURATION The Rochester Young Men's Study (n = 189) was a cross-sectional study conducted between 2009 and 2010 at the University of Rochester. PARTICIPANTS/MATERIALS, SETTING, METHODS Men aged 18–22 years were included in this analysis. Diet was assessed via food frequency questionnaire. Linear regression was used to analyze the relation between dairy intake and conventional semen quality parameters (total sperm count, sperm concentration, progressive motility, morphology and ejaculate volume) adjusting for age, abstinence time, race, smoking status, body mass index, recruitment period, moderate-to-intense exercise, TV watching and total calorie intake. MAIN RESULTS AND THE ROLE OF CHANCE Total dairy food intake was inversely related to sperm morphology (P-trend = 0.004). This association was mostly driven by intake of full-fat dairy foods. The adjusted difference (95% confidence interval) in normal sperm morphology percent was −3.2% (−4.5 to −1.8) between men in the upper half and those in the lower half of full-fat dairy intake (P < 0.0001), while the equivalent contrast for low-fat dairy intake was less pronounced [−1.3% (−2.7 to −0.07; P= 0.06)]. Full-fat dairy intake was also associated with significantly lower percent progressively motile sperm (P= 0.05). LIMITATIONS, REASONS FOR CAUTION As it was a cross-sectional study, causal inference is limited. WIDER IMPLICATIONS OF THE FINDINGS Further research is needed to prove a causal link between a high consumption of full-fat dairy foods and detrimental effects on semen quality. If verified our findings would mean that intake of full-fat dairy foods should be considered in attempts to explain secular trends in semen quality and that men trying to have children should restrict their intake. STUDY FUNDING/COMPETING INTEREST(S) European Union Seventh Framework Program (Environment), ‘Developmental Effects of Environment on Reproductive Health’ (DEER) grant 212844. Grant P30 {"type":"entrez-nucleotide","attrs":{"text":"DK046200","term_id":"187635970","term_text":"DK046200"}}DK046200 and Ruth L. Kirschstein National Research Service Award T32 DK007703-16 from the National Institutes of Health. None of the authors has any conflicts of interest to declare. |
nfcorpus-qrel-MED-1774 | Generate text that best answers this question: saturated fat | A national survey of persistent, bioaccumulative, and toxic (PBT) pollutants in the United States milk supply.
This study measured 21 persistent, bioaccumulative, and toxic (PBT) pollutants in the US milk supply. Since milk fat is likely to be among the highest dietary sources of exposure to PBTs, it is important to understand their levels in this food. Nationwide samples were collected from 45 dairy plants in July of 2000 and again in January 2001. The levels of all chemicals in the chlorobenzene, pesticide and other halogenated organic groups were determined to be below their detection limits in all samples. National averages were computed for 11 chemicals or chemical groups found above the detection limits. The national average CDD/CDF and PCB TEQ concentrations were 14.30 and 8.64 pg/l, respectively, for a total of 22.94 pg/l. These levels are about half the values found in a similar study conducted in 1996. If this difference is in fact indicative of declining milk levels and assuming exposure levels from nondairy pathways have remained the same over this time period, this would result in an overall decrease in adult background dioxin exposure of 14%. Six PAHs were detected with national averages ranging from 40 to 777 ng/l. Cadmium concentrations ranged from 150 to 870 ng/l with a national average of 360 ng/l. Lead concentrations were consistently higher than those of cadmium, ranging from 630 to 1950 ng/l with a national average of 830 ng/l. PAHs showed the strongest seasonal/geographic differences, with higher levels in winter than summer, north than south and east than west. Average adult daily intakes from total milk fat ingestion were computed for all detected compounds and compared to total intakes from all pathways: CDD/CDF/PCB TEQs: 8 vs. 55 pg/day, PAHs: 0.6 vs. 3 micro g/day, lead: 0.14 vs. 4-6 micro g/day, and cadmium: 0.06 vs. 30 micro g/day. |
nfcorpus-qrel-MED-1775 | Generate text that best answers this question: saturated fat | Comparison of individual antioxidants of sperm and seminal plasma in fertile and infertile men.
OBJECTIVE: To measure individual antioxidants in sperm and seminal plasma from fertile and infertile men to determine if any particular antioxidant is reduced in infertile men. DESIGN: Semen samples were prepared by a discontinuous Percoll gradient to separate sperm and seminal plasma, and the antioxidant concentrations of each were assessed. Samples also were screened for phorbol ester-induced reactive oxygen species (ROS) activity. SETTING: Departments of Obstetrics and Gynaecology, and Clinical Biochemistry, The Queen's University of Belfast, Northern Ireland. PATIENT(S): Fifty-nine male patients attending our infertility center: 18 men whose wives had ongoing pregnancies from IVF with normozoospermic semen profiles, 20 infertile men with normozoospermic and 21 men with asthenozoospermic semen profiles. MAIN OUTCOME MEASURE(S): Ascorbate, urate, sulphydryl groups, tocopherol and carotenoid concentrations were measured in sperm and seminal plasma from fertile and infertile men. RESULT(S): In seminal plasma, ascorbate contributes almost twice as much as urate and thiol levels are about one third of ascorbate. Ascorbate levels in seminal plasma of asthenozoospermic individuals (+ROS) are significantly reduced. In sperm, thiols contributed most and ascorbate only a fraction of the total. CONCLUSION(S): In seminal plasma, ascorbate, urates, and thiols are the major antioxidants present. In contrast, within sperm, this group is the major contributor. In samples exhibiting ROS activity, ascorbate concentrations in the seminal plasma are significantly reduced. |
nfcorpus-qrel-MED-1776 | Generate text that best answers this question: saturated fat | Semen quality trends in French regions are consistent with a global change in environmental exposure.
A retrospective study carried out recently in a large sample of men, close to the general population, has reported a significant and strong decline in sperm concentration and morphology in the whole of France between 1989 and 2005. We studied these trends within each region of France. Data were obtained from the Fivnat database. The study sample comprised male partners of sterile women in whom both tubes were absent or blocked. They were located at the assisted reproductive technology center. A Bayesian spatio-temporal model with parametric time trends, adjusted for age, was used to model overall time trends for each region. The results show that sperm concentration decreased in almost all regions of France. Among them, Aquitaine showed the highest decrease and Midi-Pyrénées had the lowest average for the whole period. Regarding total motility, most regions showed a slight increase while Bourgogne showed a steep and significant decrease. While considering sperm morphology, there was a decrease in most of the regions. The decrease in Aquitaine and Midi-Pyrénées was stronger when compared with the overall trend. In conclusion, a decrease in sperm concentration and morphology, already shown at the French metropolitan territory level, was observed in most regions of France. This is consistent with a global change in environmental exposure, according to the endocrine disruptor hypothesis especially. Indeed, ubiquitary exposure to chemicals has been growing in the general population of France since the 1950s, and the results do not appear to support the lifestyle hypothesis. The highest decreases and lowest values are consistently observed in two proximate regions that are both highly agricultural and densely populated. |
nfcorpus-qrel-MED-1777 | Generate text that best answers this question: saturated fat | Shedding Light on the Controversy Surrounding the Temporal Decline in Human Sperm Counts: A Systematic Review
We systematically examined the evidence of declining sperm counts and the hypothesis that an increased exposure to environmental pollutants is responsible for such decline. Search engines, including PUBMED, MEDLINE, EMBASE, BIOSIS, and Cochrane library, were used to identify epidemiologic studies published from 1985 to 2013. We concluded that there is no enough evidence to confirm a worldwide decline in sperm counts. Also, there seems to be no scientific truth of a causative role for endocrine disruptors in the temporal decline of sperm production. Such assumptions are based on few meta-analyses and retrospective studies, while other well-conducted researches could not confirm these findings. We acknowledge that difficult-to-control confounding factors in the highly variable nature of semen, selection criteria, and comparability of populations from different time periods in secular-trend studies, the quality of laboratory methods for counting sperm, and apparently geographic variations in semen quality are the main issues that complicate the interpretation of the available evidence. Owing to the importance of this subject and the uncertainties still prevailing, there is a need not only for continuing monitoring of semen quality, reproductive hormones, and xenobiotics, but also for a better definition of fecundity. |
nfcorpus-qrel-MED-1779 | Generate text that best answers this question: saturated fat | The reactive oxygen species-total antioxidant capacity score is a new measure of oxidative stress to predict male infertility.
The imbalance between reactive oxygen species (ROS) production and total antioxidant capacity (TAC) in seminal fluid indicates oxidative stress and is correlated with male infertility. A composite ROS-TAC score may be more strongly correlated with infertility than ROS or TAC alone. We measured ROS, TAC, and ROS-TAC scores in semen from 127 patients and 24 healthy controls. Of the patients, 56 had varicocele, eight had varicocele with prostatitis, 35 had vasectomy reversals, and 28 had idiopathic infertility. ROS levels were higher among infertile men, especially those with varicocele with prostatitis (mean +/- SE, 3.25 +/- 0.89) and vasectomy reversals (2.65 +/- 1.01). All infertile groups had significantly lower ROS-TAC scores than control. ROS-TAC score identified 80% of patients and was significantly better than ROS at identifying varicocele and idiopathic infertility. The 13 patients whose partners later achieved pregnancies had a mean ROS-TAC score of 47.7 +/- 13.2, similar to controls but significantly higher than the 39 patients who remained infertile (35.8 +/- 15.0; P < 0.01). ROS-TAC score is a novel measure of oxidative stress and is superior to ROS or TAC alone in discriminating between fertile and infertile men. Infertile men with male factor or idiopathic diagnoses had significantly lower ROS-TAC scores than controls, and men with male factor diagnoses that eventually were able to initiate a successful pregnancy had significantly higher ROS-TAC scores than those who failed. |
nfcorpus-qrel-MED-1780 | Generate text that best answers this question: saturated fat | What has happened to human fertility?
Semen quality appears to have declined in recent decades in some populations, e.g. north-western Europe. At the same time, couple fertility may have increased. Hypotheses are suggested for this apparent inconsistency. Alongside the deterioration of spermatogenesis there is clear evidence of an increase in other related problems, notably testicular cancer. The sharply rising trend in this condition started a century ago--decades earlier than sometimes thought. This and other evidence clearly indicates an environmental origin, but there is also a definite genetic component. The relationship of genetics and environment is discussed in the context of the puzzle that infertility is inherited, which appears to be impossible from an evolutionary standpoint. Poor semen quality is related not only to testicular cancer but also to zygote development, in which cancer-like disruption of the genetic apparatus is observed, with serious implications for offspring health. This needs to be seen in the context that human reproduction is prone to a higher degree of impairment than that of other mammalian species, in relation to spermatogenesis, couple fertility, early pregnancy loss and embryonic aneuploidy; female- and male-mediated pathways are both implicated. It is unclear whether such human specificity originated on an evolutionary/genetic or a historico-social timescale, which is important in relation to pathogenesis. The evidence clearly indicates that the currently most popular explanation for male reproductive system impairment, the endocrine disruption hypothesis, cannot explain the main features of the descriptive epidemiology. An alternative pathogenesis is outlined, and some possible exposures considered that could be responsible. |
nfcorpus-qrel-MED-1782 | Generate text that best answers this question: saturated fat | Antioxidants to reduce sperm DNA fragmentation: an unexpected adverse effect.
Reactive oxygen species (ROS) have a negative impact on sperm DNA, leading to the formation of oxidative products such as 8-oxo-7,8-dihydroxyguanosine. This compound causes fragmentation and, thus, has a mutagenic effect. Patient treatment with oral antioxidant vitamins is, therefore, standard practice for male infertility, in an attempt to decrease formation of ROS and improve fertility. In this study, the DNA fragmentation index and the degree of sperm decondensation were measured using the sperm chromatin structure assay before and after 90 days treatment with antioxidant vitamins associated with zinc and selenium. Antioxidant treatment led to a decrease in sperm DNA fragmentation (-19.1%, P < 0.0004), suggesting that at least part of the decay was linked to ROS. However, it also led to an unexpected negative effect: an increase in sperm decondensation with the same order of magnitude (+22.8%, P < 0.0009). The opening of interchain disulphide bridges in protamines may explain this aspect, as antioxidant vitamins, especially vitamin C, are able to open the cystin net, thus interfering with paternal gene activity during preimplantation development. This observation might explain the discrepancy observed concerning the role of these antioxidant treatments in improving male fertility. |
nfcorpus-qrel-MED-1783 | Generate text that best answers this question: saturated fat | SEMEN QUALITY IN RELATION TO ANTIOXIDANT INTAKE IN A HEALTHY MALE POPULATION
Objective To assess the relationship between dietary antioxidant intake and semen quality in young healthy males Design Cross-sectional study Setting University and college campuses in the Rochester, New York, area Patients 189 university-aged men Interventions None Main Outcome Measures Semen volume, total sperm count, concentration, motility, total motile count, and morphology Results Progressive motility was 6.5 (95% CI 0.6, 12.3) percentage units higher among men in the highest quartile of β-carotene intake compared to men in the lowest quartile. Similar results were observed for lutein intake. Lycopene intake was positively related to sperm morphology. The adjusted percentages (95% CI) of morphologically normal sperm in increasing quartiles of lycopene intake were 8.0 (6.7, 9.3), 7.7 (6.4, 9.0), 9.2 (7.9, 10.5) and 9.7 (8.4, 11.0). There was a non-linear relationship between vitamin C intake and sperm concentration, with men in the second quartile of intake having, on average, the highest sperm concentrations and men in the top quartile of intake having the lowest concentrations. Conclusions In a population of healthy young men, carotenoid intake was associated with higher sperm motility and, in the case of lycopene, better sperm morphology. Our data suggest that dietary carotenoids may have a positive impact on semen quality. |
nfcorpus-qrel-MED-1784 | Generate text that best answers this question: saturated fat | Association between sperm quality, oxidative stress, and seminal antioxidant activity.
OBJECTIVES: To determine seminal antioxidant capacity, oxidative stress markers, and their association with semen quality as oxidative stress is considered to be a major etiological factor in male infertility. SUBJECTS AND METHODS: Semen samples were obtained from 138 men and categorized on the basis of sperm count, motility, and morphology. Seminal oxidative and antioxidant markers are as follows: lipid peroxidation (LPO), protein carbonyls (PC), superoxide dismutase (SOD), catalase (CAT), thiols, and ascorbic acid were determined. RESULTS: Sperm count significantly correlated positively with progressive sperm motility and normal morphology. Sperm count and normal morphology showed significant negative correlation with LPO and PC. Sperm count and progressive motility showed significant positive relationship with SOD. The SOD, CAT, and thiols positively whereas LPO and PC negatively associated with elevated sperm count. CONCLUSION: Insufficient antioxidant enzymes and increased oxidative stress may attribute to the risk of declining semen quality and hence protective role for antioxidant enzymes against the oxidative damage cannot be ruled out. Copyright © 2010 The Canadian Society of Clinical Chemists. Published by Elsevier Inc. All rights reserved. |
nfcorpus-qrel-MED-1785 | Generate text that best answers this question: saturated fat | Walnuts improve semen quality in men consuming a Western-style diet: randomized control dietary intervention trial.
We tested the hypothesis that 75 g of whole-shelled walnuts/day added to the Western-style diet of healthy young men would beneficially affect semen quality. A randomized, parallel two-group dietary intervention trial with single-blind masking of outcome assessors was conducted with 117 healthy men, age 21-35 yr old, who routinely consumed a Western-style diet. The primary outcome was improvement in conventional semen parameters and sperm aneuploidy from baseline to 12 wk. Secondary endpoints included blood serum and sperm fatty acid (FA) profiles, sex hormones, and serum folate. The group consuming walnuts (n = 59) experienced improvement in sperm vitality, motility, and morphology, but no change was seen in the group continuing their usual diet but avoiding tree nuts (n = 58). Comparing differences between the groups from baseline, significance was found for vitality (P = 0.003), motility (P = 0.009), and morphology (normal forms; P = 0.04). Serum FA profiles improved in the walnut group with increases in omega-6 (P = 0.0004) and omega-3 (P = 0.0007) but not in the control group. The plant source of omega-3, alpha-linolenic acid (ALA) increased (P = 0.0001). Sperm aneuploidy was inversely correlated with sperm ALA, particularly sex chromosome nullisomy (Spearman correlation, -0.41, P = 0.002). Findings demonstrated that walnuts added to a Western-style diet improved sperm vitality, motility, and morphology. |
nfcorpus-qrel-MED-1786 | Generate text that best answers this question: saturated fat | Good semen quality and life expectancy: a cohort study of 43,277 men.
Fertility status may predict later mortality, but no studies have examined the effect of semen quality on subsequent mortality. Men referred to the Copenhagen Sperm Analysis Laboratory by general practitioners and urologists from 1963 to 2001 were, through a unique personal identification number, linked to the Danish central registers that hold information on all cases of cancer, causes of death, and number of children in the Danish population. The men were followed until December 31, 2001, death, or censoring, whichever occurred first, and the total mortality and cause-specific mortality of the cohort were compared with those of all age-standardized Danish men or according to semen characteristics. Among 43,277 men without azospermia referred for infertility problems, mortality decreased as the sperm concentration increased up to a threshold of 40 million/mL. As the percentages of motile and morphologically normal spermatozoa and semen volume increased, mortality decreased in a dose-response manner (P(trend) < 0.05). The decrease in mortality among men with good semen quality was due to a decrease in a wide range of diseases and was found among men both with and without children; therefore, the decrease in mortality could not be attributed solely to lifestyle and/or social factors. Semen quality may therefore be a fundamental biomarker of overall male health. |
nfcorpus-qrel-MED-1787 | Generate text that best answers this question: saturated fat | Evidence for decreasing quality of semen during past 50 years.
OBJECTIVE: To investigate whether semen quality has changed during the past 50 years. DESIGN: Review of publications on semen quality in men without a history of infertility selected by means of Cumulated Index Medicus and Current List (1930-1965) and MEDLINE Silver Platter database (1966-August 1991). SUBJECTS: 14,947 men included in a total of 61 papers published between 1938 and 1991. MAIN OUTCOME MEASURES: Mean sperm density and mean seminal volume. RESULTS: Linear regression of data weighted by number of men in each study showed a significant decrease in mean sperm count from 113 x 10(6)/ml in 1940 to 66 x 10(6)/ml in 1990 (p < 0.0001) and in seminal volume from 3.40 ml to 2.75 ml (p = 0.027), indicating an even more pronounced decrease in sperm production than expressed by the decline in sperm density. CONCLUSIONS: There has been a genuine decline in semen quality over the past 50 years. As male fertility is to some extent correlated with sperm count the results may reflect an overall reduction in male fertility. The biological significance of these changes is emphasised by a concomitant increase in the incidence of genitourinary abnormalities such as testicular cancer and possibly also cryptorchidism and hypospadias, suggesting a growing impact of factors with serious effects on male gonadal function. |
nfcorpus-qrel-MED-1788 | Generate text that best answers this question: saturated fat | Micronutrients intake is associated with improved sperm DNA quality in older men.
OBJECTIVE: To investigate whether lifestyle factors such as increased dietary intake of micronutrients reduce the risks of sperm DNA damage, and whether older men benefit more than younger men. DESIGN: Cross-sectional study design with equalized assignments into age groups. SETTING: National laboratory and university. PATIENT(S): Nonclinical group of 22-80-year-old nonsmoking men (n = 80) who reported no fertility problems. MAIN OUTCOME MEASURE(S): Sperm DNA damage measured by alkaline and neutral DNA electrophoresis (i.e., sperm Comet assay). RESULT(S): Sociodemographics, occupational exposures, medical and reproductive histories, and lifestyle habits were determined by questionnaire. The average daily dietary and supplement intake of micronutrients (vitamin C, vitamin E, b-carotene, zinc, and folate) was determined using the 100-item Modified Block Food Frequency Questionnaire (FFQ). Men with the highest intake of vitamin C had approximately 16% less sperm DNA damage (alkaline sperm Comet) than men with the lowest intake, with similar findings for vitamin E, folate, and zinc (but not β-carotene). Older men (>44 years) with the highest vitamin C intake had approximately 20% less sperm DNA damage compared with older men with the lowest intake, with similar findings for vitamin E and zinc. The older men with the highest intake of these micronutrients showed levels of sperm damage that were similar to those of the younger men. However, younger men (<44 years) did not benefit from higher intakes of the micronutrients surveyed. CONCLUSION(S): Men with higher dietary and supplement intake of certain micronutrients may produce sperm with less DNA damage, especially among older men. This raises the broader question of how lifestyle factors, including higher intakes of antioxidants and micronutrients, might protect somatic as well as germ cells against age-associated genomic damage. Copyright © 2012. Published by Elsevier Inc. |
nfcorpus-qrel-MED-1992 | Generate text that best answers this question: saturated fat | Prediabetes: A high-risk state for developing diabetes
Summary Prediabetes (or “intermediate hyperglycaemia”), based on glycaemic parameters above normal but below diabetes thresholds is a high risk state for diabetes with an annualized conversion rate of 5%–10%; with similar proportion converting back to normoglycaemia. The prevalence of prediabetes is increasing worldwide and it is projected that >470 million people will have prediabetes in 2030. Prediabetes is associated with the simultaneous presence of insulin resistance and β-cell dysfunction, abnormalities that start before glucose changes are detectable. Observational evidence shows associations of prediabetes with early forms of nephropathy, chronic kidney disease, small fibre neuropathy, diabetic retinopathy, and increased risk of macrovascular disease. Multifactorial risk scores could optimize the estimation of diabetes risk using non-invasive parameters and blood-based metabolic traits in addition to glycaemic values. For prediabetic individuals, lifestyle modification is the cornerstone of diabetes prevention with evidence of a 40%–70% relative risk reduction. Accumulating data also suggests potential benefits from pharmacotherapy. |
nfcorpus-qrel-MED-1876 | Generate text that best answers this question: saturated fat | Consumption of whole grain reduces risk of deteriorating glucose tolerance, including progression to prediabetes.
BACKGROUND: High whole-grain intake has been reportedly associated with reduced risk of developing type 2 diabetes (T2D), which is an effect possibly subject to genetic effect modification. Confirmation in prospective studies and investigations on the impact on prediabetes is needed. OBJECTIVES: In a prospective population-based study, we investigated whether a higher intake of whole grain protects against the development of prediabetes and T2D and tested for modulation by polymorphisms of the TCF7L2 gene. DESIGN: We examined the 8-10-y incidence of prediabetes (impaired glucose tolerance, impaired fasting glucose, or the combination of both) and T2D in relation to the intake of whole grain. Baseline data were available for 3180 women and 2297 men aged 35-56 y. RESULTS: A higher intake of whole grain (>59.1 compared with <30.6 g/d) was associated with a 34% lower risk to deteriorate in glucose tolerance (to prediabetes or T2D; women and men combined). The association remained after adjustments for age, family history of diabetes, BMI, physical activity, smoking, education, and blood pressure (OR: 0.78; 95% CI: 0.63, 0.96). Risk reduction was significant in men (OR: 0.65; 95% CI: 0.49, 0.85) but not in women. Associations were significant for prediabetes per se (all, OR: 0.73; 95% CI: 0.56, 0.94; men, OR: 0.57; 95% CI: 0.40, 0.80). The intake of whole grain correlated inversely with insulin resistance (HOMA-IR). The impact of whole-grain intake was undetectable in men who harbored diabetogenic polymorphisms of the TCF7L2 gene. CONCLUSIONS: A higher intake of whole grain is associated with decreased risk of deteriorating glucose tolerance including progression from normal glucose tolerance to prediabetes by mechanisms likely tied to effects on insulin sensitivity. Effect modifications by TCF7L2 genetic polymorphisms are supported. |
nfcorpus-qrel-MED-1998 | Generate text that best answers this question: saturated fat | The early treatment of type 2 diabetes.
The growing epidemic of type 2 diabetes is one of the leading causes of premature morbidity and mortality worldwide, mainly due to the micro- and macrovascular complications associated with the disease. A growing body of evidence suggests that although the risk of developing complications is greater with glucose levels beyond the established threshold for diagnosis--increasing in parallel with rising hyperglycemia-individuals with glucose levels in the prediabetic range are already at increased risk. Early intervention, ideally as soon as abnormalities in glucose homeostasis are detected, is of great importance to minimize the burden of the disease. However, as the early stages of the disease are asymptomatic, diagnosing prediabetes and early overt type 2 diabetes is challenging. The aim of this article is to discuss these challenges, the benefits of early intervention--with emphasis on the prevention trials showing that progression to type 2 diabetes can be delayed by addressing prediabetes--and the existing evidence-based guidelines that have been drawn to optimize the standards of care at the prediabetes and overt type 2 diabetes stages. Copyright © 2013. Published by Elsevier Inc. |
nfcorpus-qrel-MED-1878 | Generate text that best answers this question: saturated fat | Crossing the Quality Chasm: A New Health System for the 21st Century
Excerpt Second in a series of publications from the Institute of Medicine's Quality of Health Care in America project Today's health care providers have more research findings and more technology available to them than ever before. Yet recent reports have raised serious doubts about the quality of health care in America. Crossing the Quality Chasm makes an urgent call for fundamental change to close the quality gap. This book recommends a sweeping redesign of the American health care system and provides overarching principles for specific direction for policymakers, health care leaders, clinicians, regulators, purchasers, and others. In this comprehensive volume the committee offers: A set of performance expectations for the 21st century health care system. A set of 10 new rules to guide patient-clinician relationships. A suggested organizing framework to better align the incentives inherent in payment and accountability with improvements in quality. Key steps to promote evidence-based practice and strengthen clinical information systems. Analyzing health care organizations as complex systems, Crossing the Quality Chasm also documents the causes of the quality gap, identifies current practices that impede quality care, and explores how systems approaches can be used to implement change. Copyright 2001 by the National Academy of Sciences. All rights reserved. |
nfcorpus-qrel-MED-1879 | Generate text that best answers this question: saturated fat | Daily flaxseed consumption improves glycemic control in obese men and women with pre-diabetes: a randomized study.
The study hypothesis was that fasting glucose, insulin, fructosamine, C-reactive protein, and interleukin-6 decrease and adiponectin increases with daily flaxseed consumption in overweight or obese individuals with pre-diabetes. In this randomized, cross-over study overweight or obese men and postmenopausal women (n = 25) with pre-diabetes consumed 0, 13, or 26 g ground flaxseed for 12 weeks. Glucose, insulin, homeostatic model assessment (HOMA-IR), and normalized percent of α-linolenic fatty acid (ALA) were significantly different by treatment (multiple analysis of variance, P = .036, P = .013, P = .008, P = .024 respectively). Paired t tests showed glucose decreased on the 13 g intervention compared to the 0 g period [13 g = -2.10 ± 1.66 mg/L (mean ± SEM), 0 g = 9.22 ± 4.44 mg/L, P = .036]. Insulin decreased on the 13 g intervention but not the 26 g (P = .021) and 0 g (P = .013) periods (13 g = -2.12 ± 1.00 mU/L, 26 g = 0.67 ± 0.84 mU/L, 0 g = 1.20 ± 1.16 mU/L). HOMA-IR decreased on the 13 g period but not on the 26 g (P = .012) and 0 g (P = .008) periods (13 g = -0.71 ± 0.31, 26 g = 0.27 ± 0.24, 0 g = 0.51 ± 0.35). The α-linolenic fatty acid decrease for the 0 g period was different than the 13 g (P = .024) and 26 g (P = .000) periods (13 g = 0.20 ± 0.04, 26 g = 0.35 ± 0.07, 0 g = -0.01 ± 0.07). Fructosamine, high sensitivity C-reactive protein, adiponectin, and high-sensitivity interleukin-6 had no significant differences. Flaxseed intake decreased glucose and insulin and improved insulin sensitivity as part of a habitual diet in overweight or obese individuals with pre-diabetes. Copyright © 2013 Elsevier Inc. All rights reserved. |
nfcorpus-qrel-MED-1914 | Generate text that best answers this question: saturated fat | Early life stress and telomere length: Investigating the connection and possible mechanisms
How can adverse experiences in early life, such as maltreatment, exert such powerful negative effects on health decades later? The answer may lie in changes to DNA. New research suggests that exposure to stress can accelerate the erosion of DNA segments called telomeres. Shorter telomere length correlates with chronological age and also disease morbidity and mortality. Thus, telomere erosion is a potential mechanism linking childhood stress to health problems later in life. However, an array of mechanistic, methodological, and basic biological questions must be addressed in order to translate telomere discoveries into clinical applications for monitoring health and predicting disease risk. This paper covers the current state of the science and lays out new research directions. |
nfcorpus-qrel-MED-1915 | Generate text that best answers this question: saturated fat | Work-Related Exhaustion and Telomere Length: A Population-Based Study
Background Psychological stress is suggested to accelerate the rate of biological aging. We investigated whether work-related exhaustion, an indicator of prolonged work stress, is associated with accelerated biological aging, as indicated by shorter leukocyte telomeres, that is, the DNA-protein complexes that cap chromosomal ends in cells. Methods We used data from a representative sample of the Finnish working-age population, the Health 2000 Study. Our sample consisted of 2911 men and women aged 30–64. Work-related exhaustion was assessed using the Maslach Burnout Inventory - General Survey. We determined relative leukocyte telomere length using a quantitative real-time polymerase chain reaction (PCR) -based method. Results After adjustment for age and sex, individuals with severe exhaustion had leukocyte telomeres on average 0.043 relative units shorter (standard error of the mean 0.016) than those with no exhaustion (p = 0.009). The association between exhaustion and relative telomere length remained significant after additional adjustment for marital and socioeconomic status, smoking, body mass index, and morbidities (adjusted difference 0.044 relative units, standard error of the mean 0.017, p = 0.008). Conclusions These data suggest that work-related exhaustion is related to the acceleration of the rate of biological aging. This hypothesis awaits confirmation in a prospective study measuring changes in relative telomere length over time. |
nfcorpus-qrel-MED-1916 | Generate text that best answers this question: saturated fat | The association between physical activity in leisure time and leukocyte telomere length.
BACKGROUND: Physical inactivity is an important risk factor for many aging-related diseases. Leukocyte telomere dynamics (telomere length and age-dependent attrition rate) are ostensibly a biological indicator of human aging. We therefore tested the hypothesis that physical activity level in leisure time (over the past 12 months) is associated with leukocyte telomere length (LTL) in normal healthy volunteers. METHODS: We studied 2401 white twin volunteers, comprising 2152 women and 249 men, with questionnaires on physical activity level, smoking status, and socioeconomic status. Leukocyte telomere length was derived from the mean terminal restriction fragment length and adjusted for age and other potential confounders. RESULTS: Leukocyte telomere length was positively associated with increasing physical activity level in leisure time (P< .001); this association remained significant after adjustment for age, sex, body mass index, smoking, socioeconomic status, and physical activity at work. The LTLs of the most active subjects were 200 nucleotides longer than those of the least active subjects (7.1 and 6.9 kilobases, respectively; P= .006). This finding was confirmed in a small group of twin pairs discordant for physical activity level (on average, the LTL of more active twins was 88 nucleotides longer than that of less active twins; P= .03). CONCLUSIONS: A sedentary lifestyle (in addition to smoking, high body mass index, and low socioeconomic status) has an effect on LTL and may accelerate the aging process. This provides a powerful message that could be used by clinicians to promote the potentially antiaging effect of regular exercise. |
nfcorpus-qrel-MED-1917 | Generate text that best answers this question: saturated fat | Effect of healthy lifestyle behaviors on the association between leukocyte telomere length and coronary artery calcium.
The telomere length is an indicator of biologic aging, and shorter telomeres have been associated with coronary artery calcium (CAC), a validated indicator of coronary atherosclerosis. It is unclear, however, whether healthy lifestyle behaviors affect the relation between telomere length and CAC. In a sample of subjects aged 40 to 64 years with no previous diagnosis of coronary heart disease, stroke, diabetes mellitus, or cancer (n = 318), healthy lifestyle behaviors of greater fruit and vegetable consumption, lower meat consumption, exercise, being at a healthy weight, and the presence of social support were examined to determine whether they attenuated the association between a shorter telomere length and the presence of CAC. Logistic regression analyses controlling for age, gender, race/ethnicity, and Framingham risk score revealed that the relation between having shorter telomeres and the presence of CAC was attenuated in the presence of high social support, low meat consumption, and high fruit and vegetable consumption. Those with shorter telomeres and these characteristics were not significantly different from those with longer telomeres. Conversely, the subjects with shorter telomeres and less healthy lifestyles had a significantly increased risk of the presence of CAC: low fruit and vegetable consumption (odds ratio 3.30, 95% confidence interval 1.61 to 6.75), high meat consumption (odds ratio 3.33, 95% confidence interval 1.54 to 7.20), and low social support (odds ratio 2.58, 95% confidence interval 1.24 to 5.37). Stratification by gender yielded similar results for men; however, among women, only fruit and vegetable consumption attenuated the shorter telomere length and CAC relation. In conclusion, the results of the present study suggest that being involved in healthy lifestyle behaviors might attenuate the association between shorter telomere length and coronary atherosclerosis, as identified using CAC. 2010 Elsevier Inc. All rights reserved. |
nfcorpus-qrel-MED-1918 | Generate text that best answers this question: saturated fat | Intensive meditation training, immune cell telomerase activity, and psychological mediators.
BACKGROUND: Telomerase activity is a predictor of long-term cellular viability, which decreases with chronic psychological distress (Epel et al., 2004). Buddhist traditions claim that meditation decreases psychological distress and promotes well-being (e.g., Dalai Lama and Cutler, 2009). Therefore, we investigated the effects of a 3-month meditation retreat on telomerase activity and two major contributors to the experience of stress: Perceived Control (associated with decreased stress) and Neuroticism (associated with increased subjective distress). We used mediation models to test whether changes in Perceived Control and Neuroticism explained meditation retreat effects on telomerase activity. In addition, we investigated whether two qualities developed by meditative practice, increased Mindfulness and Purpose in Life, accounted for retreat-related changes in the two stress-related variables and in telomerase activity. METHODS: Retreat participants (n=30) meditated for ∼6 h daily for 3 months and were compared with a wait-list control group (n=30) matched for age, sex, body mass index, and prior meditation experience. Retreat participants received instruction in concentrative meditation techniques and complementary practices used to cultivate benevolent states of mind (Wallace, 2006). Psychological measures were assessed pre- and post-retreat. Peripheral blood mononuclear cell samples were collected post-retreat for telomerase activity. Because there were clear, a priori hypotheses, 1-tailed significance criteria were used throughout. RESULTS: Telomerase activity was significantly greater in retreat participants than in controls at the end of the retreat (p<0.05). Increases in Perceived Control, decreases in Neuroticism, and increases in both Mindfulness and Purpose in Life were greater in the retreat group (p<0.01). Mediation analyses indicated that the effect of the retreat on telomerase was mediated by increased Perceived Control and decreased Neuroticism. In turn, changes in Perceived Control and Neuroticism were both partially mediated by increased Mindfulness and Purpose in Life. Additionally, increases in Purpose in Life directly mediated the telomerase group difference, whereas increases in Mindfulness did not. CONCLUSIONS: This is the first study to link meditation and positive psychological change with telomerase activity. Although we did not measure baseline telomerase activity, the data suggest that increases in perceived control and decreases in negative affectivity contributed to an increase in telomerase activity, with implications for telomere length and immune cell longevity. Further, Purpose in Life is influenced by meditative practice and directly affects both perceived control and negative emotionality, affecting telomerase activity directly as well as indirectly. Copyright © 2010 Elsevier Ltd. All rights reserved. |
nfcorpus-qrel-MED-1919 | Generate text that best answers this question: saturated fat | Human telomerase model shows the role of the TEN domain in advancing the double helix for the next polymerization step
Telomerases constitute a group of specialized ribonucleoprotein enzymes that remediate chromosomal shrinkage resulting from the “end-replication” problem. Defects in telomere length regulation are associated with several diseases as well as with aging and cancer. Despite significant progress in understanding the roles of telomerase, the complete structure of the human telomerase enzyme bound to telomeric DNA remains elusive, with the detailed molecular mechanism of telomere elongation still unknown. By application of computational methods for distant homology detection, comparative modeling, and molecular docking, guided by available experimental data, we have generated a three-dimensional structural model of a partial telomerase elongation complex composed of three essential protein domains bound to a single-stranded telomeric DNA sequence in the form of a heteroduplex with the template region of the human RNA subunit, TER. This model provides a structural mechanism for the processivity of telomerase and offers new insights into elongation. We conclude that the RNA∶DNA heteroduplex is constrained by the telomerase TEN domain through repeated extension cycles and that the TEN domain controls the process by moving the template ahead one base at a time by translation and rotation of the double helix. The RNA region directly following the template can bind complementarily to the newly synthesized telomeric DNA, while the template itself is reused in the telomerase active site during the next reaction cycle. This first structural model of the human telomerase enzyme provides many details of the molecular mechanism of telomerase and immediately provides an important target for rational drug design. |
nfcorpus-qrel-MED-1920 | Generate text that best answers this question: saturated fat | Look AHEAD (Action for Health in Diabetes): design and methods for a clinical trial of weight loss for the prevention of cardiovascular disease in ...
Overweight and obesity are major contributors to both type 2 diabetes and cardiovascular disease (CVD). Moreover, individuals with type 2 diabetes who are overweight or obese are at particularly high risk for CVD morbidity and mortality. Although short-term weight loss has been shown to ameliorate obesity-related metabolic abnormalities and CVD risk factors, the long-term consequences of intentional weight loss in overweight or obese individuals with type 2 diabetes have not been adequately examined. The primary objective of the Look AHEAD clinical trial is to assess the long-term effects (up to 11.5 years) of an intensive weight loss program delivered over 4 years in overweight and obese individuals with type 2 diabetes. Approximately 5000 male and female participants who have type 2 diabetes, are 45-74 years of age, and have a body mass index >or=25 kg/m(2) will be randomized to one of the two groups. The intensive lifestyle intervention is designed to achieve and maintain weight loss through decreased caloric intake and increased physical activity. This program is compared to a control condition given diabetes support and education. The primary study outcome is time to incidence of a major CVD event. The study is designed to provide a 0.90 probability of detecting an 18% difference in major CVD event rates between the two groups. Other outcomes include components of CVD risk, cost and cost-effectiveness, diabetes control and complications, hospitalizations, intervention processes, and quality of life. |
nfcorpus-qrel-MED-1921 | Generate text that best answers this question: saturated fat | Intake of Small-to-Medium-Chain Saturated Fatty Acids Is Associated with Peripheral Leukocyte Telomere Length in Postmenopausal Women
Dietary factors, including dietary fat, may affect the biological aging process, as reflected by the shortening of telomere length (TL), by affecting levels of oxidative stress and inflammatory responses. We examined the direct relations of total and types of dietary fats and fat-rich foods to peripheral leukocyte TL. In 4029 apparently healthy postmenopausal women who participated in the Women’s Health Initiative, intakes of total fat, individual fatty acids, and fat-rich foods were assessed by a questionnaire. TL was measured by quantitative polymerase chain reaction. Intake of short-to-medium-chain saturated fatty acids (SMSFAs; aliphatic tails of ≤12 carbons) was inversely associated with TL. Compared with participants in other quartiles of SMSFA intake, women who were in the highest quartile (median: 1.29% of energy) had shorter TLs [mean: 4.00 kb (95% CI: 3.89, 4.11 kb)], whereas women in the lowest quartile of intake (median: 0.29% of energy) had longer TLs [mean: 4.13 kb (95% CI: 4.03, 4.24 kb); P-trend = 0.046]. Except for lauric acid, all other individual SMSFAs were inversely associated with TL (P < 0.05). In isoenergetic substitution models, the substitution of 1% of energy from SMSFAs with any other energy source was associated with 119 bp longer TLs (95% CI: 21, 216 bp). Intakes of nonskim milk, butter, and whole-milk cheese (major sources of SMSFAs) were all inversely associated with TL. No significant associations were found with long-chain saturated fatty acids, monounsaturated fatty acids, and polyunsaturated fatty acids. In conclusion, we found that higher intakes of SMSFAs and SMSFA-rich foods were associated with shorter peripheral leukocyte TL among postmenopausal women. These findings suggest the potential roles of SMSFAs in the rate of biological aging. |
nfcorpus-qrel-MED-1922 | Generate text that best answers this question: saturated fat | Stress and Telomere Biology: A Lifespan Perspective
In the past decade, the growing field of telomere science has opened exciting new avenues for understanding the cellular and molecular substrates of stress and stress-related aging processes ver the lifespan. Shorter telomere length is associated with advancing chronological age and also increased disease morbidity and mortality. Emerging studies suggest that stress accelerates the erosion of telomeres from very early in life and possibly even influences the initial (newborn) setting of telomere length. In this review, we highlight recent empirical evidence linking stress and mental illnesses at various times across the lifespan with telomere erosion. We first present findings in the developmental programming of telomere biology linking prenatal stress to newborn and adult telomere length. We then present findings linking exposure to childhood trauma and to certain mental disorders with telomere shortening. Last, we review studies that characterize the relationship between related health-risk behaviors with telomere shortening over the lifespan, and how this process may further buffer the negative effects of stress on telomeres. A better understanding of the mechanisms that govern and regulate telomere biology throughout the lifespan may inform our understanding of etiology and the long-term consequences of stress and mental illnesses on aging processes in diverse populations and settings. |
nfcorpus-qrel-MED-1923 | Generate text that best answers this question: saturated fat | Loving-Kindness Meditation practice associated with longer telomeres in women.
Relatively short telomere length may serve as a marker of accelerated aging, and shorter telomeres have been linked to chronic stress. Specific lifestyle behaviors that can mitigate the effects of stress might be associated with longer telomere lengths. Previous research suggests a link between behaviors that focus on the well-being of others, such as volunteering and caregiving, and overall health and longevity. We examined relative telomere length in a group of individuals experienced in Loving-Kindness Meditation (LKM), a practice derived from the Buddhist tradition which utilizes a focus on unselfish kindness and warmth towards all people, and control participants who had done no meditation. Blood was collected by venipuncture, and Genomic DNA was extracted from peripheral blood leukocytes. Quantitative real time PCR was used to measure relative telomere length (RTL) (Cawthon, 2002) in fifteen LKM practitioners and 22 control participants. There were no significant differences in age, gender, race, education, or exposure to trauma, but the control group had a higher mean body mass index (BMI) and lower rates of past depression. The LKM practitioners had longer RTL than controls at the trend level (p=.083); among women, the LKM practitioners had significantly longer RTL than controls, (p=.007), which remained significant even after controlling for BMI and past depression. Although limited by small sample size, these results offer the intriguing possibility that LKM practice, especially in women, might alter RTL, a biomarker associated with longevity. Copyright © 2013 Elsevier Inc. All rights reserved. |
nfcorpus-qrel-MED-1924 | Generate text that best answers this question: saturated fat | Saturated fatty acid metabolism is key link between cell division, cancer, and senescence in cellular and whole organism aging
Cellular senescence is an in vivo and in vitro phenomenon, accompanied by physiological changes including cessation of division and disturbances of organelle structure and function. Review of the literature was undertaken to determine whether there is evidence that whole organism aging and cell senescence share a common initiation pathway. In vivo aged cells of different lineages, including aged T lymphocytes, show high expression of the INK4A-p16 gene. In cell culture when telomeres are shortened past a key length or state, the Arf/Ink gene system (p16/p14 humans, p16/p19 mice) switches on and activates p53, which suppresses further cell division. The p53 gene is a key tumor suppressor and its deletion or mutation allows cancerous growth. The switching on of p53 also causes changes in fatty acid metabolism, especially down-regulation of both fatty acid synthase and stearoyl-CoA (delta-9) desaturase. The co-suppression of these genes together with enhanced uptake of extracellular fatty acids, leads to raised levels of cellular palmitate and induction of either apoptosis or senescence. In senescent cells, the fatty acid composition of the cellular membranes alters and leads to changes in both structure and function of organelles, especially mitochondria. Animal models of accelerated aging exhibit repression of stearoyl-CoA desaturase activity while anti-aging calorie restriction stimulates the same enzyme system. It is concluded that aging in cells and whole organisms share a common initiation pathway and that cellular senescence is protective against cancer. Healthy longevity is likely to be most enhanced by factors that actively suppress excessive cell division. |
nfcorpus-qrel-MED-4877 | Generate text that best answers this question: saturated fat | Increased telomerase activity and comprehensive lifestyle changes: a pilot study.
BACKGROUND: Telomeres are protective DNA-protein complexes at the end of linear chromosomes that promote chromosomal stability. Telomere shortness in human beings is emerging as a prognostic marker of disease risk, progression, and premature mortality in many types of cancer, including breast, prostate, colorectal, bladder, head and neck, lung, and renal cell. Telomere shortening is counteracted by the cellular enzyme telomerase. Lifestyle factors known to promote cancer and cardiovascular disease might also adversely affect telomerase function. However, previous studies have not addressed whether improvements in nutrition and lifestyle are associated with increases in telomerase activity. We aimed to assess whether 3 months of intensive lifestyle changes increased telomerase activity in peripheral blood mononuclear cells (PBMC). METHODS: 30 men with biopsy-diagnosed low-risk prostate cancer were asked to make comprehensive lifestyle changes. The primary endpoint was telomerase enzymatic activity per viable cell, measured at baseline and after 3 months. 24 patients had sufficient PBMCs needed for longitudinal analysis. This study is registered on the ClinicalTrials.gov website, number NCT00739791. FINDINGS: PBMC telomerase activity expressed as natural logarithms increased from 2.00 (SD 0.44) to 2.22 (SD 0.49; p=0.031). Raw values of telomerase increased from 8.05 (SD 3.50) standard arbitrary units to 10.38 (SD 6.01) standard arbitrary units. The increases in telomerase activity were significantly associated with decreases in low-density lipoprotein (LDL) cholesterol (r=-0.36, p=0.041) and decreases in psychological distress (r=-0.35, p=0.047). INTERPRETATION: Comprehensive lifestyle changes significantly increase telomerase activity and consequently telomere maintenance capacity in human immune-system cells. Given this finding and the pilot nature of this study, we report these increases in telomerase activity as a significant association rather than inferring causation. Larger randomised controlled trials are warranted to confirm the findings of this study. |
nfcorpus-qrel-MED-1926 | Generate text that best answers this question: saturated fat | Habitual physical exercise has beneficial effects on telomere length in postmenopausal women.
OBJECTIVE: It has been reported that women benefit from the maintenance of telomere length by estrogen. Exercise may favorably influence telomere length, although results are inconsistent regarding the duration and type of exercise and the cell type used to measure telomere length. The purpose of this study was to investigate the relationship between habitual physical exercise and telomere length in peripheral blood mononuclear cells (PBMCs) in postmenopausal women. Postmenopausal women were chosen as study participants because they are typically estrogen deficient. METHODS: This experimental-control, cross-sectional study included 44 healthy, nondiabetic, nonsmoking, postmenopausal women. Habitual exercisers and sedentary participants were matched for age and body mass index. Body weight, height, blood pressure, and waist and hip circumference were measured. Mitochondrial DNA copy number and telomere length in PBMCs were determined, and biochemical tests were performed. Habitual physical exercise was defined as combined aerobic and resistance exercise performed for at least 60 minutes per session more than three times a week for more than 12 months. RESULTS: The mean age of all participants was 58.11 ± 6.84 years, and participants in the habitual exercise group had been exercising more than three times per week for an average of 19.23 ± 5.15 months. Serum triglyceride levels (P = 0.01), fasting insulin concentrations (P < 0.01), and homeostasis model assessment of insulin resistance (P < 0.01) were significantly lower and high-density lipoprotein cholesterol levels (P < 0.01), circulating adiponectin (P < 0.01), mitochondrial DNA copy number (P < 0.01), and telomere length (P < 0.01) were significantly higher in the habitual exercise group than in the sedentary group. In a stepwise multiple regression analysis, habitual exercise (β = 0.522, P < 0.01) and adiponectin levels (β = 0.139, P = 0.03) were the independent factors associated with the telomere length of PBMCs in postmenopausal women. CONCLUSIONS: Habitual physical exercise is associated with greater telomere length in postmenopausal women. This finding suggests that habitual physical exercise in postmenopausal women may reduce telomere attrition. |
nfcorpus-qrel-MED-4878 | Generate text that best answers this question: saturated fat | Dietary patterns, food groups, and telomere length in the Multi-Ethnic Study of Atherosclerosis (MESA)
Background Telomere length reflects biological aging and may be influenced by environmental factors, including those that affect inflammatory processes. Objective With data from 840 white, black, and Hispanic adults from the Multi-Ethnic Study of Atherosclerosis, we studied cross-sectional associations between telomere length and dietary patterns and foods and beverages that were associated with markers of inflammation. Design Leukocyte telomere length was measured by quantitative polymerase chain reaction. Length was calculated as the amount of telomeric DNA (T) divided by the amount of a single-copy control DNA (S) (T/S ratio). Intake of whole grains, fruit and vegetables, low-fat dairy, nuts or seeds, nonfried fish, coffee, refined grains, fried foods, red meat, processed meat, and sugar-sweetened soda were computed with responses to a 120-item food-frequency questionnaire completed at baseline. Scores on 2 previously defined empirical dietary patterns were also computed for each participant. Results After adjustment for age, other demographics, lifestyle factors, and intakes of other foods or beverages, only processed meat intake was associated with telomere length. For every 1 serving/d greater intake of processed meat, the T/S ratio was 0.07 smaller (β ± SE: −0.07 ± 0.03, P = 0.006). Categorical analysis showed that participants consuming ≥1 serving of processed meat each week had 0.017 smaller T/S ratios than did nonconsumers. Other foods or beverages and the 2 dietary patterns were not associated with telomere length. Conclusions Processed meat intake showed an expected inverse association with telomere length, but other diet features did not show their expected associations. |
nfcorpus-qrel-MED-1928 | Generate text that best answers this question: saturated fat | Telomeres, lifestyle, cancer, and aging
Purpose of review There has been growing evidence that lifestyle factors may affect the health and lifespan of an individual by affecting telomere length. The purpose of this review was to highlight the importance of telomeres in human health and aging and to summarize possible lifestyle factors that may affect health and longevity by altering the rate of telomere shortening. Recent findings Recent studies indicate that telomere length, which can be affected by various lifestyle factors, can affect the pace of aging and onset of age-associated diseases. Summary Telomere length shortens with age. Progressive shortening of telomeres leads to senescence, apoptosis, or oncogenic transformation of somatic cells, affecting the health and lifespan of an individual. Shorter telomeres have been associated with increased incidence of diseases and poor survival. The rate of telomere shortening can be either increased or decreased by specific lifestyle factors. Better choice of diet and activities has great potential to reduce the rate of telomere shortening or at least prevent excessive telomere attrition, leading to delayed onset of age-associated diseases and increased lifespan. This review highlights the role of telomeres in aging and describes the lifestyle factors which may affect telomeres, human health, and aging. |
nfcorpus-qrel-MED-1929 | Generate text that best answers this question: saturated fat | A pilot study of yogic meditation for family dementia caregivers with depressive symptoms: Effects on mental health, cognition, and telomerase activity
BACKGROUND This study examined the effects of brief daily yogic meditation on mental health, cognitive functioning, and immune cell telomerase activity in family dementia caregivers with mild depressive symptoms. METHODS Thirty-nine family dementia caregivers (mean age 60.3 years old (SD=10.2)) were randomized to practicing Kirtan Kriya or listening to relaxation music for 12 minutes per day for eight weeks. The severity of depressive symptoms, mental and cognitive functioning were assessed at baseline and follow-up. Telomerase activity in peripheral blood mononuclear cells (PMBC) was examined in peripheral PBMC pre- and post-intervention. RESULTS The meditation group showed significantly lower levels of depressive symptoms and greater improvement in mental health and cognitive functioning compared to the relaxation group. In the meditation group, 65.2% showed 50% improvement on the Hamilton Depression Rating scale and 52% of the participants showed 50% improvement on the Mental Health Composite Summary score (MCS) of the SF-36 scale; compared to 31.2% and 19% respectively in the relaxation group (pp<0.05). The meditation group showed 43% improvement in telomerase activity compared to 3.7% in the relaxation group (p=0.05). CONCLUSION This pilot study found that brief daily meditation practices by family dementia caregivers can lead to improved mental and cognitive functioning, and lower levels of depressive symptoms. This improvement is accompanied by an increase in telomerase activity suggesting improvement in stress-induced cellular aging. These results need to be confirmed in a larger sample. |
nfcorpus-qrel-MED-1930 | Generate text that best answers this question: saturated fat | Leukocyte telomere length and its relation to food and nutrient intake in an elderly population.
BACKGROUND/OBJECTIVES: Shorter leukocyte telomere length (LTL) is associated with several chronic diseases, but only a few studies have assessed the association between dietary factors and LTL. Our objective was to study the association between fats, fruits, vegetables and LTL in a cross-sectional study design. We hypothesized that intakes of fruits and vegetables would be positively associated with LTL and that intakes of fats, and especially saturated fatty acids (SFAs), would be negatively associated with LTL. SUBJECTS/METHODS: LTL was measured by quantitative real-time polymerase chain reaction in 1942 men and women aged 57-70 years from the Helsinki Birth Cohort Study. We assessed the whole diet by a validated semiquantitative 128-item food-frequency questionnaire. RESULTS: In general, there were only a few significant results. However, total fat and SFA intake (P=0.04 and 0.01, respectively) were inversely associated with LTL in men adjusting for age and energy intake. In women, vegetable intake was positively associated with LTL (P=0.05). Men consuming the most butter and least fruits had significantly shorter telomeres than those consuming the lowest amounts of butter and highest amounts of fruits (P=0.05). We found no association between LTL and body mass index, waist-hip ratio, smoking, physical activity or educational attainment. CONCLUSIONS: In this cross-sectional study of elderly men and women, there were only a few statistically significant effects of diet, but in general they support the hypothesis that fat and vegetable intakes were associated with LTL. |
nfcorpus-qrel-MED-1931 | Generate text that best answers this question: saturated fat | Accelerated Telomere Erosion Is Associated with a Declining Immune Function of Caregivers of Alzheimer’s Disease Patients
Caregivers of Alzheimer’s disease patients endure chronic stress associated with a decline of immune function. To assess the psychological and immunological changes of caregivers, we compared depressive symptoms, PBMC composition, in vitro activation-induced proliferation and cytokine production, and telomere length and telomerase activity of 82 individuals (41 caregivers and 41 age- and gender-matched controls). We found depressive symptoms were significantly higher in caregivers than in controls (p < 0.001). Correspondingly, caregivers had significantly lower T cell proliferation but higher production of immune-regulatory cytokines (TNF-α and IL-10) than controls in response to stimulation in vitro. We examined the impact of these changes on cellular replicative lifespan and found that caregivers had significantly shorter telomere lengths in PBMC than controls (6.2 and 6.4 kb, respectively, p < 0.05) with similar shortening in isolated T cells and monocytes and that this telomere attrition in caregivers was not due to an increase of shorter telomere possessing T cell subsets in PBMC. Finally, we showed that basal telomerase activity in PBMC and T cells was significantly higher in caregivers than in controls (p < 0.0001), pointing to an unsuccessful attempt of cells to compensate the excessive loss of telomeres in caregivers. These findings demonstrate that chronic stress is associated with altered T cell function and accelerated immune cell aging as suggested by excessive telomere loss. |
nfcorpus-qrel-MED-1932 | Generate text that best answers this question: saturated fat | Exposure to violence during childhood is associated with telomere erosion from 5 to 10 years of age: a longitudinal study
There is increasing interest in discovering mechanisms that mediate the effects of childhood stress on late-life disease morbidity and mortality. Previous studies have suggested one potential mechanism linking stress to cellular aging, disease and mortality in humans: telomere erosion. We examined telomere erosion in relation to children’s exposure to violence, a salient early-life stressor, which has known long-term consequences for well-being and is a major public-health and social-welfare problem. In the first prospective-longitudinal study with repeated telomere measurements in children while they experienced stress, we tested the hypothesis that childhood violence exposure would accelerate telomere erosion from age 5 to age 10 years. Violence was assessed as exposure to maternal domestic violence, frequent bullying victimization and physical maltreatment by an adult. Participants were 236 children (49% females; 42% with one or more violence exposures) recruited from the Environmental-Risk Longitudinal Twin Study, a nationally representative 1994–1995 birth cohort. Each child’s mean relative telomere length was measured simultaneously in baseline and follow-up DNA samples, using the quantitative PCR method for T/S ratio (the ratio of telomere repeat copy numbers to single-copy gene numbers). Compared with their counterparts, the children who experienced two or more kinds of violence exposure showed significantly more telomere erosion between age-5 baseline and age-10 follow-up measurements, even after adjusting for sex, socioeconomic status and body mass index (B = −0.052, s.e. = 0.021, P = 0.015). This finding provides support for a mechanism linking cumulative childhood stress to telomere maintenance, observed already at a young age, with potential impact for life-long health. |
nfcorpus-qrel-MED-1933 | Generate text that best answers this question: saturated fat | From the Cover: Accelerated telomere shortening in response to life stress
Numerous studies demonstrate links between chronic stress and indices of poor health, including risk factors for cardiovascular disease and poorer immune function. Nevertheless, the exact mechanisms of how stress gets “under the skin” remain elusive. We investigated the hypothesis that stress impacts health by modulating the rate of cellular aging. Here we provide evidence that psychological stress— both perceived stress and chronicity of stress—is significantly associated with higher oxidative stress, lower telomerase activity, and shorter telomere length, which are known determinants of cell senescence and longevity, in peripheral blood mononuclear cells from healthy premenopausal women. Women with the highest levels of perceived stress have telomeres shorter on average by the equivalent of at least one decade of additional aging compared to low stress women. These findings have implications for understanding how, at the cellular level, stress may promote earlier onset of age-related diseases. |
nfcorpus-qrel-MED-1934 | Generate text that best answers this question: saturated fat | Independent and Combined Effects of Dietary Weight Loss and Exercise on Leukocyte Telomere Length in Postmenopausal Women
Objective Investigate the effects of 12 months of dietary weight loss and/or aerobic exercise on leukocyte telomere length in postmenopausal women. Design and Methods 439 overweight or obese women (50–75 y) were randomized to: i) dietary weight loss (N=118); ii) aerobic exercise (N=117), iii) diet + exercise (N=117), or iv) control (N=87). The diet intervention was a group-based program with a 10% weight loss goal. The exercise intervention was 45 mins/day, 5 days/week of moderate-to-vigorous aerobic activity. Fasting blood samples were taken at baseline and 12 months. DNA was extracted from isolated leukocytes and telomere length was measured by quantitative-polymerase chain reaction (qPCR). Mean changes were compared between groups (intent-to-treat) using generalized estimating equations. Results Baseline telomere length was inversely associated with age (r=−0.12 p<0.01) and positively associated with maximal oxygen uptake (r=0.11, p=0.03), but not with BMI or %body fat. Change in telomere length was inversely correlated with baseline telomere length (r=−0.47, p<0.0001). No significant difference in leukocyte telomere length was detected in any intervention group compared to controls, nor was the magnitude of weight loss associated with telomere length at 12 months. Conclusions Twelve-months of dietary weight loss and exercise did not change telomere length in postmenopausal women. |
nfcorpus-qrel-MED-1935 | Generate text that best answers this question: saturated fat | Diet-related telomere shortening and chromosome stability
Recent evidences have highlighted an influence of micronutrients in the maintenance of telomere length (TL). In order to explore whether diet-related telomere shortening had any physiological relevance and was accompanied by significant damage in the genome, in the present study, TL was assessed by terminal restriction fragment (TRF) analysis in peripheral blood lymphocytes of 56 healthy subjects for which detailed information on dietary habits was available and data were compared \with the incidence of nucleoplasmic bridges (NPBs), a marker of chromosomal instability related to telomere dysfunction visualised with the cytokinesis-blocked micronucleus assay. To increase the capability to detect even slight impairment of telomere function, the incidence of NPBs was also evaluated on cells exposed in vitro to ionising radiation. Care was taken to control for potential confounding factors that might influence TL, viz. age, hTERT genotype and smoking status. Data showed that higher consumption of vegetables was related with significantly higher mean TL (P = 0.013); in particular, the analysis of the association between micronutrients and mean TL highlighted a significant role of antioxidant intake, especially beta-carotene, on telomere maintenance (P = 0.004). However, the diet-related telomere shortening did not result in associated increased spontaneous or radiation-induced NPBs. The distribution of TRFs was also analysed and a slight prevalence of radiation-induced NPBs (P = 0.03) was observed in subjects with higher amount of very short TRFs (<2 kb). The relative incidence of very short TRFs was positively associate with ageing (P = 0.008) but unrelated to vegetables consumption and daily intake of micronutrients, suggesting that the degree of telomere erosion related with low dietary intake of antioxidants observed in this study was not so extensive to lead to chromosome instability. |
nfcorpus-qrel-MED-1936 | Generate text that best answers this question: saturated fat | Physical exercise prevents cellular senescence in circulating leukocytes and in the vessel wall.
BACKGROUND: The underlying molecular mechanisms of the vasculoprotective effects of physical exercise are incompletely understood. Telomere erosion is a central component of aging, and telomere-associated proteins regulate cellular senescence and survival. This study examines the effects of exercising on vascular telomere biology and endothelial apoptosis in mice and the effects of long-term endurance training on telomere biology in humans. METHODS AND RESULTS: C57/Bl6 mice were randomized to voluntary running or no running wheel conditions for 3 weeks. Exercise upregulated telomerase activity in the thoracic aorta and in circulating mononuclear cells compared with sedentary controls, increased vascular expression of telomere repeat-binding factor 2 and Ku70, and reduced the expression of vascular apoptosis regulators such as cell-cycle-checkpoint kinase 2, p16, and p53. Mice preconditioned by voluntary running exhibited a marked reduction in lipopolysaccharide-induced aortic endothelial apoptosis. Transgenic mouse studies showed that endothelial nitric oxide synthase and telomerase reverse transcriptase synergize to confer endothelial stress resistance after physical activity. To test the significance of these data in humans, telomere biology in circulating leukocytes of young and middle-aged track and field athletes was analyzed. Peripheral blood leukocytes isolated from endurance athletes showed increased telomerase activity, expression of telomere-stabilizing proteins, and downregulation of cell-cycle inhibitors compared with untrained individuals. Long-term endurance training was associated with reduced leukocyte telomere erosion compared with untrained controls. CONCLUSIONS: Physical activity regulates telomere-stabilizing proteins in mice and in humans and thereby protects from stress-induced vascular apoptosis. |
nfcorpus-qrel-MED-1949 | Generate text that best answers this question: saturated fat | Is very preterm birth a risk factor for adult cardiometabolic disease?
The first infants to experience modern pre- and neonatal care are now in their thirties, an age at which the incidence of cardiometabolic disease is low. However, data from cohorts born preterm prior to the introduction of modern care suggest an increased risk of type 2 diabetes. For young adult cohorts of former very small or very preterm infants, there is accumulating evidence of increased risk factors for later cardiovascular disease, including higher blood pressure, lower lean body mass, impaired glucose regulation, and perhaps a more atherogenic lipid profile. Regarding lifestyle, adults born very small or very preterm undertake less non-conditioning physical activity and may have a lower intake of fruit and milk products. Any intervention reducing risk factors, in particular blood pressure and low physical activity, would have a substantial potential to reduce the lifetime disease burden in small preterm infants. There are now enough data to warrant an expert evaluation of the level of evidence for cardiometabolic disease in individuals born very small or very preterm, which has possible public health implications. Copyright © 2013 Elsevier Ltd. All rights reserved. |
nfcorpus-qrel-MED-1950 | Generate text that best answers this question: saturated fat | Intakes of Garlic and Dried Fruits Are Associated with Lower Risk of Spontaneous Preterm Delivery
Several studies have found associations between microbial infections during pregnancy and preterm delivery (PTD). We investigated the influence of food with antimicrobial and prebiotic components on the risk of spontaneous PTD. A literature search identified microbes associated with spontaneous PTD. Subsequently, 2 main food types (alliums and dried fruits) were identified to contain antimicrobial components that affect the microbes associated with spontaneous PTD; they also contained dietary fibers recognized as prebiotics. We investigated intake in 18,888 women in the Norwegian Mother and Child Cohort (MoBa), of whom 950 (5%) underwent spontaneous PTD (<37 gestational weeks). Alliums (garlic, onion, leek, and spring onion) [OR: 0.82 (95% CI: 0.72, 0.94), P = 0.005] and dried fruits (raisins, apricots, prunes, figs, and dates) [OR: 0.82 (95% CI: 0.72, 0.94); P = 0.005] were associated with a decreased risk of spontaneous PTD. Intake of alliums was related to a more pronounced risk reduction in early spontaneous PTD (gestational weeks 28–31) [OR: 0.39 (95% CI: 0.19, 0.80)]. The strongest association in this group was with garlic [OR: 0.47 (95% CI: 0.25–0.89)], followed by cooked onions. Intake of dried fruits showed an association with preterm prelabor rupture of membranes (PPROM) [OR: 0.74 (95% CI: 0.65, 0.95)]; the strongest association in this group was with raisins [OR: 0.71 (95% CI: 0.56, 0.92)]. The strongest association with PPROM in the allium group was with garlic [OR: 0.74 (95% CI: 0.56, 0.97)]. In conclusion, intake of food with antimicrobial and prebiotic compounds may be of importance to reduce the risk of spontaneous PTD. In particular, garlic was associated with overall lower risk of spontaneous PTD. Dried fruits, especially raisins, were associated with reduced risk of PPROM. |
nfcorpus-qrel-MED-1951 | Generate text that best answers this question: saturated fat | Late preterm birth: a review of medical and neuropsychological childhood outcomes.
Late preterm (LP) birth (34 0/7 - 36 6/7 weeks' gestation) accounts for nearly three-fourths of all preterm births, making this population a sizeable public health concern. The immature fetal development associated with LP delivery increases the risk of mortality and short-term medical complications. Which combination of maternal, fetal, or neonatal risk factors may be most critical has only recently begun to be addressed, and whether LP birth's disruptive impact on brain development will exert adverse effects on neuropsychological functioning in childhood and adolescence has been understudied. Early data have shown a graded response, with LP children often functioning better than very preterm children but worse than term children, and with subtle intellectual and neuropsychological deficits in LP children compared with healthy children born at term gestational age. Further characterization of the neuropsychological profile is required and would be best accomplished through prospective longitudinal studies. Moreover, since moderate and LP births result in disparate medical and psychological outcomes, the common methodology of combining these participants into a single research cohort to assess risk and outcome should be reconsidered. The rapidly growing LP outcomes literature reinforces a critical principle: fetal development occurs along a dynamic maturational continuum from conception to birth, with each successive gestational day likely to improve overall outcome. |
nfcorpus-qrel-MED-1952 | Generate text that best answers this question: saturated fat | Growing up after extremely preterm birth: lifespan mental health outcomes.
There is growing interest in the long-term mental health sequelae of extremely preterm birth. In this paper we review literature relating to mental health outcomes across the lifespan. Studies conducted in the preschool years, school age and adolescence, and adulthood show continuity in outcomes and point to an increased risk for inattention, socio-communicative problems and emotional difficulties in individuals born extremely preterm. Both behavioural and neuroimaging studies also provide evidence of a neurodevelopmental origin for mental health disorders in this population. Here we summarise contemporary evidence and highlight key methodological considerations for carrying out and interpreting studies in this field. Copyright © 2013 Elsevier Ltd. All rights reserved. |
nfcorpus-qrel-MED-1953 | Generate text that best answers this question: saturated fat | Antimicrobial properties of Allium sativum (garlic).
Although garlic has been used for its medicinal properties for thousands of years, investigations into its mode of action are relatively recent. Garlic has a wide spectrum of actions; not only is it antibacterial, antiviral, antifungal and antiprotozoal, but it also has beneficial effects on the cardiovascular and immune systems. Resurgence in the use of natural herbal alternatives has brought the use of medicinal plants to the forefront of pharmacological investigations, and many new drugs are being discovered. This review aims to address the historical use of garlic and its sulfur chemistry, and to provide a basis for further research into its antimicrobial properties. |
nfcorpus-qrel-MED-1954 | Generate text that best answers this question: saturated fat | Preterm birth and behaviour problems in infants and preschool-age children: a review of the recent literature.
The behaviour problems of children born preterm at school age are well known, but there have been few studies on the behaviour problems of preterm-born infants during infancy and at preschool age. Fourteen cohort studies published in PubMed and PsycINFO between 2000 and 2012 were reviewed with a focus on the type, occurrence, comorbidity, stability, prediction, perinatal, social, and relational risk factors for behaviour problems of preterm-born children in infancy (0-2y) and at preschool age (3-5y). The relational risk factor was considered in an additional four papers. Very-preterm, very-low-birthweight, and moderately-preterm children, in both age groups, show more behaviour problems than term-born comparison children even after perinatal and social risk factors and cognitive performance have been controlled for. Poor social/interactive skills, poor behavioural and emotional self-regulation, emotional difficulties, and reduced attention are the most common behaviour problems. Behaviour problems in infancy are predictive of later behaviour problems and they should be included in follow-up programmes. © The Authors. Developmental Medicine & Child Neurology © 2013 Mac Keith Press. |
nfcorpus-qrel-MED-1955 | Generate text that best answers this question: saturated fat | Maternal dietary patterns and preterm delivery: results from large prospective cohort study
Objective To examine whether an association exists between maternal dietary patterns and risk of preterm delivery. Design Prospective cohort study. Setting Norway, between 2002 and 2008. Participants 66 000 pregnant women (singletons, answered food frequency questionnaire, no missing information about parity or previously preterm delivery, pregnancy duration between 22+0 and 41+6 gestational weeks, no diabetes, first enrolment pregnancy). Main outcome measure Hazard ratio for preterm delivery according to level of adherence to three distinct dietary patterns interpreted as “prudent” (for example, vegetables, fruits, oils, water as beverage, whole grain cereals, fibre rich bread), “Western” (salty and sweet snacks, white bread, desserts, processed meat products), and “traditional” (potatoes, fish). Results After adjustment for covariates, high scores on the “prudent” pattern were associated with significantly reduced risk of preterm delivery hazard ratio for the highest versus the lowest third (0.88, 95% confidence interval 0.80 to 0.97). The prudent pattern was also associated with a significantly lower risk of late and spontaneous preterm delivery. No independent association with preterm delivery was found for the “Western” pattern. The “traditional” pattern was associated with reduced risk of preterm delivery for the highest versus the lowest third (hazard ratio 0.91, 0.83 to 0.99). Conclusion This study showed that women adhering to a “prudent” or a “traditional” dietary pattern during pregnancy were at lower risk of preterm delivery compared with other women. Although these findings cannot establish causality, they support dietary advice to pregnant women to eat a balanced diet including vegetables, fruit, whole grains, and fish and to drink water. Our results indicate that increasing the intake of foods associated with a prudent dietary pattern is more important than totally excluding processed food, fast food, junk food, and snacks. |
nfcorpus-qrel-MED-1966 | Generate text that best answers this question: saturated fat | Effects of dietary cholesterol on serum cholesterol: a meta-analysis and review.
Attempts to estimate the effects of dietary cholesterol on serum cholesterol by meta-analysis have not previously included baseline together with added dietary cholesterol in a mathematical model. Mean reported changes in serum cholesterol from 27 studies in which controlled diets were supplied by a metabolic kitchen provided 76 data points, each weighted by the number of subjects in nonlinear regression. A good fit to the data (P less than 0.0005, and r = 0.617 between observed and predicted points) was given by the equation y = 1.22(e-0.00384 chi 0) (1-e-0.0136 chi) where y is the change in serum cholesterol (in mmol/L), chi is added dietary cholesterol, and chi 0 is baseline dietary cholesterol (both in mg/d). Possible reasons for the hyperbolic shape of the relationship between change in serum cholesterol and added dietary cholesterol, mechanisms for individual responsiveness to dietary cholesterol, and important implications regarding interpretation of prior studies and public health issues are discussed. |
nfcorpus-qrel-MED-2967 | Generate text that best answers this question: saturated fat | Atherogenesis: a postprandial phenomenon.
The hypothesis that plasma chylomicrons in persons who ingest a cholesterol-rich diet are atherogenic is evaluated. Evidence is presented that in humans, and experimental animals, chylomicron remnants as well as low-density lipoproteins are taken up by arterial cells. In persons who do not have familial hyperlipoproteinemia, atherogenesis may occur during the postprandial period. Research directions that may contribute to the evaluation of chylomicron remnants as a risk factor for atherogenesis are discussed. Lipoprotein studies after administration of a test meal containing fat and cholesterol are urgently needed. |
nfcorpus-qrel-MED-1968 | Generate text that best answers this question: saturated fat | Effects of increasing amounts of dietary cholesterol on postprandial lipemia and lipoproteins in human subjects.
Our aim was to determine the effects of increasing amounts of dietary cholesterol (0-710 mg) on the postprandial plasma lipid responses and lipoprotein changes in normolipidemic human subjects. Ten subjects were fed five different test meals in a random order: one meal did not contain fat or cholesterol while the four others contained a fixed amount of lipids (45 g) and 0, 140, 280, and 710 mg cholesterol, respectively. Fasting and post-meal blood samples were obtained for 7 h. Large and small triglyceride-rich lipoproteins (TRL), low density (LDL), and high density (HDL) lipoproteins were isolated. Compared to the no-fat, no-cholesterol meal, the fat-enriched meals raised (P < 0.05) plasma triglycerides, phospholipids, and free cholesterol and lowered cholesteryl esters postprandially. The meals containing zero or 140 mg cholesterol generally elicited comparable postprandial plasma and lipoprotein lipid responses. The meals providing 280 or 710 mg cholesterol significantly increased postprandial plasma phospholipids and large TRL triglycerides and decreased plasma esterified cholesterol. The lipid composition of the large TRLs and the concentrations of the small TRL lipid components were not altered postprandially by cholesterol intake. On the other hand, LDL free cholesterol increased after 3 h, LDL cholesteryl esters dropped after 3 and 7 h, HDL cholesteryl esters dropped after 3 h, and HDL phospholipids increased 7 h after ingesting meals highly enriched in cholesterol. Blood insulin, apoA-I and apoB were not altered postprandially by cholesterol intake. Thus, the data show that ingesting more than 140 mg cholesterol per meal significantly alters the postprandial lipoprotein response in healthy subjects. |
nfcorpus-qrel-MED-2000 | Generate text that best answers this question: saturated fat | Projection of the year 2050 burden of diabetes in the US adult population: dynamic modeling of incidence, mortality, and prediabetes prevalence
Background People with diabetes can suffer from diverse complications that seriously erode quality of life. Diabetes, costing the United States more than $174 billion per year in 2007, is expected to take an increasingly large financial toll in subsequent years. Accurate projections of diabetes burden are essential to policymakers planning for future health care needs and costs. Methods Using data on prediabetes and diabetes prevalence in the United States, forecasted incidence, and current US Census projections of mortality and migration, the authors constructed a series of dynamic models employing systems of difference equations to project the future burden of diabetes among US adults. A three-state model partitions the US population into no diabetes, undiagnosed diabetes, and diagnosed diabetes. A four-state model divides the state of "no diabetes" into high-risk (prediabetes) and low-risk (normal glucose) states. A five-state model incorporates an intervention designed to prevent or delay diabetes in adults at high risk. Results The authors project that annual diagnosed diabetes incidence (new cases) will increase from about 8 cases per 1,000 in 2008 to about 15 in 2050. Assuming low incidence and relatively high diabetes mortality, total diabetes prevalence (diagnosed and undiagnosed cases) is projected to increase from 14% in 2010 to 21% of the US adult population by 2050. However, if recent increases in diabetes incidence continue and diabetes mortality is relatively low, prevalence will increase to 33% by 2050. A middle-ground scenario projects a prevalence of 25% to 28% by 2050. Intervention can reduce, but not eliminate, increases in diabetes prevalence. Conclusions These projected increases are largely attributable to the aging of the US population, increasing numbers of members of higher-risk minority groups in the population, and people with diabetes living longer. Effective strategies will need to be undertaken to moderate the impact of these factors on national diabetes burden. Our analysis suggests that widespread implementation of reasonably effective preventive interventions focused on high-risk subgroups of the population can considerably reduce, but not eliminate, future increases in diabetes prevalence. |
nfcorpus-qrel-MED-2001 | Generate text that best answers this question: saturated fat | Awareness of prediabetes--United States, 2005-2010.
In 2010, approximately one in three U.S. adults aged≥20 years (an estimated 79 million persons) had prediabetes, a condition in which blood glucose or hemoglobin A1c (A1c) levels are higher than normal but not high enough to be classified as diabetes. Persons with prediabetes are at high risk for developing type 2 diabetes, which accounts for 90%-95% of all cases of diabetes. Each year, 11% of persons with prediabetes who do not lose weight and do not engage in moderate physical activity will progress to type 2 diabetes during the average 3 years of follow-up. Evidence-based lifestyle programs that encourage dietary changes, moderate-intensity physical activity, and modest weight loss can delay or prevent type 2 diabetes in persons with prediabetes. Identifying persons with prediabetes and informing them about their increased risk for type 2 diabetes are first steps in encouraging persons with prediabetes to make healthy lifestyle changes. However, during 2005-2006, only approximately 7% of persons with prediabetes were aware that they had prediabetes. To examine recent changes in awareness of prediabetes and factors associated with awareness among adults aged≥20 years, CDC analyzed data from the National Health and Nutrition Examination Survey (NHANES). This report describes the results of that analysis, which indicated that, during 2009-2010, approximately 11% of those with prediabetes were aware of their condition. Furthermore, during 2005-2010, estimated awareness of prediabetes was <14% across all population subgroups, different levels of health-care access or use, and other factors. In the United States, persons with prediabetes, including those with regular access to health care, might benefit from efforts aimed at making them aware that they are at risk for developing type 2 diabetes and that they can reduce that risk by making modest lifestyle changes. Efforts are needed to increase awareness. |
nfcorpus-qrel-MED-2002 | Generate text that best answers this question: saturated fat | Prevention of type 2 diabetes mellitus by changes in lifestyle among subjects with impaired glucose tolerance.
BACKGROUND: Type 2 diabetes mellitus is increasingly common, primarily because of increases in the prevalence of a sedentary lifestyle and obesity. Whether type 2 diabetes can be prevented by interventions that affect the lifestyles of subjects at high risk for the disease is not known. METHODS: We randomly assigned 522 middle-aged, overweight subjects (172 men and 350 women; mean age, 55 years; mean body-mass index [weight in kilograms divided by the square of the height in meters], 31) with impaired glucose tolerance to either the intervention group or the control group. Each subject in the intervention group received individualized counseling aimed at reducing weight, total intake of fat, and intake of saturated fat and increasing intake of fiber and physical activity. An oral glucose-tolerance test was performed annually; the diagnosis of diabetes was confirmed by a second test. The mean duration of follow-up was 3.2 years. RESULTS: The mean (+/-SD) amount of weight lost between base line and the end of year 1 was 4.2+/-5.1 kg in the intervention group and 0.8+/-3.7 kg in the control group; the net loss by the end of year 2 was 3.5+/-5.5 kg in the intervention group and 0.8+/-4.4 kg in the control group (P<0.001 for both comparisons between the groups). The cumulative incidence of diabetes after four years was 11 percent (95 percent confidence interval, 6 to 15 percent) in the intervention group and 23 percent (95 percent confidence interval, 17 to 29 percent) in the control group. During the trial, the risk of diabetes was reduced by 58 percent (P<0.001) in the intervention group. The reduction in the incidence of diabetes was directly associated with changes in lifestyle. CONCLUSIONS: Type 2 diabetes can be prevented by changes in the lifestyles of high-risk subjects. |
nfcorpus-qrel-MED-2003 | Generate text that best answers this question: saturated fat | REDUCTION IN THE INCIDENCE OF TYPE 2 DIABETES WITH LIFESTYLE INTERVENTION OR METFORMIN
Background Type 2 diabetes affects approximately 8 percent of adults in the United States. Some risk factors — elevated plasma glucose concentrations in the fasting state and after an oral glucose load, over-weight, and a sedentary lifestyle — are potentially reversible. We hypothesized that modifying these factors with a lifestyle-intervention program or the administration of metformin would prevent or delay the development of diabetes. Methods We randomly assigned 3234 nondiabetic persons with elevated fasting and post-load plasma glucose concentrations to placebo, metformin (850 mg twice daily), or a lifestyle-modification program with the goals of at least a 7 percent weight loss and at least 150 minutes of physical activity per week. The mean age of the participants was 51 years, and the mean body-mass index (the weight in kilograms divided by the square of the height in meters) was 34.0; 68 percent were women, and 45 percent were members of minority groups. Results The average follow-up was 2.8 years. The incidence of diabetes was 11.0, 7.8, and 4.8 cases per 100 person-years in the placebo, metformin, and lifestyle groups, respectively. The lifestyle intervention reduced the incidence by 58 percent (95 percent confidence interval, 48 to 66 percent) and metformin by 31 percent (95 percent confidence interval, 17 to 43 percent), as compared with placebo; the lifestyle intervention was significantly more effective than metformin. To prevent one case of diabetes during a period of three years, 6.9 persons would have to participate in the lifestyle-intervention program, and 13.9 would have to receive metformin. Conclusions Lifestyle changes and treatment with metformin both reduced the incidence of diabetes in persons at high risk. The lifestyle intervention was more effective than metformin. |
nfcorpus-qrel-MED-2004 | Generate text that best answers this question: saturated fat | Creating public awareness: state 2025 diabetes forecasts.
The incidence and prevalence of diabetes (primarily type 2 diabetes) has risen sharply since 1990. It is projected to increase another 64% between 2010 and 2025, affecting 53.1 million people and resulting in medical and societal costs of a half trillion dollars a year. We know how to prevent many cases of diabetes and how to treat it effectively. Early appropriate treatment makes a significant difference in preventing major complications and reducing premature death, but it does not cure the disease. Early detection of prediabetes, in conjunction with lifestyle changes, can reduce the number of people with diabetes. A dramatic reduction in diabetes prevalence over time will require significant lifestyle changes on the part of society as a whole. The purpose of this study is to increase public awareness of the severity of regional diabetes trends by providing detailed forecasts for all states and several metropolitan areas for 2010, 2015, and 2025. A model was created to utilize the latest national diabetes and population data and projections, and to transform these into state and metropolitan area forecasts for the whole population and major subgroups. These forecasts were then summarized in easy-to-understand briefing papers for each state and selected metro areas, which are provided online for easy public access. This research is important because little data exist that project the future prevalence and potential costs of diabetes at the state and metro area level. With this data, key stakeholders can make informed decisions concerning diabetes, its impact on their communities, and resource allocation. |
nfcorpus-qrel-MED-2005 | Generate text that best answers this question: saturated fat | Microvascular complications. Retinopathy and nephropathy.
Diabetic retinopathy and diabetic nephropathy extract an enormous toll on patients with diabetes and an enormous burden on the health care system. With aggressive control of glycemia and blood pressure, coupled with aggressive use of laser photocoagulation and treatment of microalbuminuria, these problems can largely be eliminated. In the future, specific interventions may emerge that will allow interdiction of the pathophysiologic processes that lead to initiation and progression of these microvascular complications. The challenge for the primary care physician and diabetologist is to attain excellent glycemic control and aggressive control of blood pressure, while assuring that every patient has appropriate dilated fundus examinations at least annually, preferably by an ophthalmologist or retinal specialist, and regular screening for microalbuminuria. With such medical management, appropriate intervention can occur to reduce the risk of blindness and renal failure and to lessen the burden from diabetic retinopathy and nephropathy. |
nfcorpus-qrel-MED-2006 | Generate text that best answers this question: saturated fat | Identification of peptide hormones of the amphipathic helix class using the helical hydrophobic moment algorithm.
Eisenberg's helical hydrophobic moment (less than mu H greater than) algorithm was applied to the analysis of the primary structure of amphipathic alpha-helical peptide hormones and an optimal method for identifying other peptides of this class determined. We quantitate and compare known amphipathic helical peptide hormones with a second group of peptides with proven nonamphipathic properties and determine the best method of distinguishing between them. The respective means of the maximum 11 residue less than mu H greater than for the amphipathic helical and control peptides were 0.46 (+/-/-0.07) and 0.33 (0.07) (P + 0.004). To better reflect the amphipathic potential of the entire peptide, the percent of 11 residue segments in each peptide above a particular less than mu H greater than was plotted vs less than mu H greater than. The resulting curves are referred to as HM-C. The mean HM-C (of the two groups) was highly significantly different such that the HM-C method was superior to others in its ability to distinguish amphipathic from nonamphipathic peptides. Several potential new members of this structural class were identified using this approach. Molecular modeling of a portion of one of these, prolactin inhibitory factor, reveals a strongly amphipathic alpha helix at residues 4-21. This computer-based method may enable rapid identification of peptides of the amphipathic alpha-helix class. |
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