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Nutrition Research Reviews Jun 2009The amount and type of dietary fat have long been associated with the risk of CVD. Arterial stiffness and endothelial dysfunction are important risk factors in the... (Review)
Review
The amount and type of dietary fat have long been associated with the risk of CVD. Arterial stiffness and endothelial dysfunction are important risk factors in the aetiology of CHD. A range of methods exists to assess vascular function that may be used in nutritional science, including clinic and ambulatory blood pressure monitoring, pulse wave analysis, pulse wave velocity, flow-mediated dilatation and venous occlusion plethysmography. The present review focuses on the quantity and type of dietary fat and effects on blood pressure, arterial compliance and endothelial function. Concerning fat quantity, the amount of dietary fat consumed habitually appears to have little influence on vascular function independent of fatty acid composition, although single high-fat meals postprandially impair endothelial function compared with low-fat meals. The mechanism is related to increased circulating lipoproteins and NEFA which may induce pro-inflammatory pathways and increase oxidative stress. Regarding the type of fat, cross-sectional data suggest that saturated fat adversely affects vascular function whereas polyunsaturated fat (mainly linoleic acid (18 : 2n-6) and n-3 PUFA) are beneficial. EPA (20 : 5n-3) and DHA (22 : 6n-3) can reduce blood pressure, improve arterial compliance in type 2 diabetics and dyslipidaemics, and augment endothelium-dependent vasodilation. The mechanisms for this vascular protection, and the nature of the separate physiological effects induced by EPA and DHA, are priorities for future research. Since good-quality observational or interventional data on dietary fatty acid composition and vascular function are scarce, no further recommendations can be suggested in addition to current guidelines at the present time.
Topics: Blood Pressure; Coronary Disease; Diet; Dietary Fats; Endothelium, Vascular; Fatty Acids; Fatty Acids, Nonesterified; Fatty Acids, Unsaturated; Humans; Inflammation; Lipoproteins; Oxidative Stress; Vasodilation
PubMed: 19243668
DOI: 10.1017/S095442240925846X -
Nutrients Sep 2019Lifestyle is a key modifiable risk factor involved in the manifestation of metabolic syndrome and, in particular, diet plays a pivotal role in its prevention and... (Review)
Review
Lifestyle is a key modifiable risk factor involved in the manifestation of metabolic syndrome and, in particular, diet plays a pivotal role in its prevention and development. Current dietary guidelines discourage the consumption of saturated fat and dietary sources rich in saturated fat, such as dairy products, despite data suggesting that full-fat dairy consumption is protective against metabolic syndrome. This narrative review assessed the recent epidemiological and clinical research that examined the consumption of dairy-derived saturated fatty acids (SFA) on metabolic syndrome risk. In addition, this review evaluated studies of individual SFA to gain insight into the potential mechanisms at play with intake of a diet enriched with these dairy-derived fatty acids. This work underscores that SFA are a heterogenous class of fatty acids that can differ considerably in their biological activity within the body depending on their length and specific chemical structure. In summary, previous work on the impact of dairy-derived SFA consumption on disease risk suggests that there is currently insufficient evidence to support current dietary guidelines which consolidate all dietary SFA into a single group of nutrients whose consumption should be reduced, regardless of dietary source, food matrix, and composition.
Topics: Dairy Products; Diet; Dietary Fats; Fatty Acids; Female; Humans; Male; Metabolic Syndrome; Risk Factors
PubMed: 31547352
DOI: 10.3390/nu11092200 -
American Family Physician Jan 2022
Review
Topics: Cardiovascular Diseases; Diet; Dietary Fats; Energy Intake; Fatty Acids; Fatty Acids, Unsaturated; Female; Heart Disease Risk Factors; Humans; Lipids; Male; Randomized Controlled Trials as Topic
PubMed: 35029948
DOI: No ID Found -
Journal of Internal Medicine Jul 2012The relation of dietary fat to risk of coronary heart disease (CHD) has been studied extensively using many approaches, including controlled feeding studies with... (Review)
Review
The relation of dietary fat to risk of coronary heart disease (CHD) has been studied extensively using many approaches, including controlled feeding studies with surrogate end-points such as plasma lipids, limited randomized trials and large cohort studies. All lines of evidence indicate that specific dietary fatty acids play important roles in the cause and the prevention of CHD, but total fat as a percent of energy is unimportant. Trans fatty acids from partially hydrogenated vegetable oils have clear adverse effects and should be eliminated. Modest reductions in CHD rates by further decreases in saturated fat are possible if saturated fat is replaced by a combination of poly- and mono-unsaturated fat, and the benefits of polyunsaturated fat appear strongest. However, little or no benefit is likely if saturated fat is replaced by carbohydrate, but this will in part depend on the form of carbohydrate. Because both N-6 and N-3 polyunsaturated fatty acids are essential and reduce risk of heart disease, the ratio of N-6 to N-3 is not useful and can be misleading. In practice, reducing red meat and dairy products in a food supply and increasing intakes of nuts, fish, soy products and nonhydrogenated vegetable oils will improve the mix of fatty acids and have a markedly beneficial effect on rates of CHD.
Topics: Biomarkers; Cardiovascular Diseases; Cholesterol; Cholesterol, HDL; Cholesterol, LDL; Clinical Trials as Topic; Coronary Disease; Dietary Fats; Fatty Acids, Omega-3; Fatty Acids, Omega-6; Humans; Risk Factors; Trans Fatty Acids
PubMed: 22583051
DOI: 10.1111/j.1365-2796.2012.02553.x -
The Journal of Medical Investigation :... Aug 2009Insulin resistance is one of the pathophysiological features of obesity and type 2 diabetes. Recent findings have linked insulin resistance to chronic low-grade... (Review)
Review
Insulin resistance is one of the pathophysiological features of obesity and type 2 diabetes. Recent findings have linked insulin resistance to chronic low-grade inflammation in white adipose tissue. Excess storage of saturated fat in white adipose tissue due to a modern life style causes hypertrophy and hyperplasia of adipocytes, which exhibit attenuated insulin signaling due to their production and release of saturated fatty acids. These adipocytes recruit macrophages to white adipose tissue and, together with them, initiate a proinflammatory response. Proinflammatory factors and saturated fatty acids secreted into the bloodstream from white adipose tissue impair insulin signaling in non-adipose tissues, which causes whole-body insulin resistance.
Topics: Adipose Tissue, White; Endocrine System; Energy Metabolism; Fatty Acids; Humans; Inflammation; Insulin Resistance; Macrophages; Obesity; Signal Transduction
PubMed: 19763019
DOI: 10.2152/jmi.56.88 -
The Ceylon Medical Journal Jun 2006In many areas of Sri Lanka the coconut tree and its products have for centuries been an integral part of life, and it has come to be called the "Tree of life". However,...
In many areas of Sri Lanka the coconut tree and its products have for centuries been an integral part of life, and it has come to be called the "Tree of life". However, in the last few decades, the relationship between coconut fats and health has been the subject of much debate and misinformation. Coconut fats account for 80% of the fat intake among Sri Lankans. Around 92% of these fats are saturated fats. This has lead to the belief that coconut fats are 'bad for health', particularly in relation to ischaemic heart disease. Yet most of the saturated fats in coconut are medium chain fatty acids whose properties and metabolism are different to those of animal origin. Medium chain fatty acids do not undergo degradation and re-esterification processes and are directly used in the body to produce energy. They are not as 'bad for health' as saturated fats. There is the need to clarify issues relating to intake of coconut fats and health, more particularly for populations that still depend on coconut fats for much of their fat intake. This paper describes the metabolism of coconut fats and its potential benefits, and attempts to highlight its benefits to remove certain misconceptions regarding its use.
Topics: Cardiovascular Diseases; Coconut Oil; Fatty Acids; Health Knowledge, Attitudes, Practice; Humans; Nutritional Status; Plant Oils; Risk Assessment; Risk Factors; Sri Lanka
PubMed: 17180807
DOI: 10.4038/cmj.v51i2.1351 -
PloS One 2017Elevated cholesterol has been linked to cardiovascular disease in adults and preclinical markers of atherosclerosis in children, thus reducing saturated (SFA) and... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
Elevated cholesterol has been linked to cardiovascular disease in adults and preclinical markers of atherosclerosis in children, thus reducing saturated (SFA) and trans-fatty acids (TFA) intake from an early age may help to reduce cholesterol and the risk of cardiovascular disease later in life. The aim of this review is to examine the evidence for health effects associated with reducing SFA and TFA intake in free-living children, adolescents and young adults between 2 to 19 years of age.
DESIGN
Systematic review and meta-analysis of randomised controlled trials (RCTs) and prospective cohort studies. Study selection, assessment, validity, data extraction, and analysis were undertaken as specified by the Cochrane Collaboration and the GRADE working group. Data were pooled using inverse variance models with random effects.
DATA SOURCES
EMBASE; PubMed; Cochrane Central Register of Controlled Trials; LILACS; and WHO Clinical Trial Registry (up to July 2016).
ELIGIBILITY CRITERIA FOR SELECTING TRIALS
RCTs involving dietary interventions aiming to reduce SFA or TFA intakes and a control group, and cohort studies reporting the effects of SFA or TFA exposures, on outcomes including blood lipids; measures of growth; blood pressure; insulin resistance; and potential adverse effects. Minimum duration was 13 days for RCTs and one year for cohort studies. Trials of weight loss or confounded by additional medical or lifestyle interventions were excluded.
RESULTS
Compared with control diets, there was a highly statistically significant effect of reduced SFA intake on total cholesterol (mean difference (MD) -0.16 mmol/l, [95% confidence interval (CI): -0.25 to -0.07]), LDL cholesterol (MD -0.13 mmol/l [95% CI:-0.22 to -0.03]) and diastolic blood pressure (MD -1.45 mmol/l [95% CI:-2.34 to -0.56]). There were no significant effects on any other risk factors and no evidence of adverse effects.
CONCLUSIONS
Advice to reduce saturated fatty acids intake of children results in a significant reduction in total and LDL-cholesterol levels as well as diastolic blood pressure without evidence of adverse effects on growth and development. Dietary guidelines for children and adolescents should continue to recommend diets low in saturated fat.
Topics: Adolescent; Child; Child, Preschool; Fatty Acids; Humans; Trans Fatty Acids
PubMed: 29149184
DOI: 10.1371/journal.pone.0186672 -
Journal of Atherosclerosis and... May 2018The associations between dietary saturated fatty acids and the risks of stroke subtypes in cohort studies were examined by a meta-analysis of separate ethnic Japanese... (Meta-Analysis)
Meta-Analysis Review
High Dietary Saturated Fat is Associated with a Low Risk of Intracerebral Hemorrhage and Ischemic Stroke in Japanese but not in Non-Japanese: A Review and Meta-Analysis of Prospective Cohort Studies.
AIM
The associations between dietary saturated fatty acids and the risks of stroke subtypes in cohort studies were examined by a meta-analysis of separate ethnic Japanese and non-Japanese cohorts, and causes of their difference were elucidated.
METHOD
Log hazard ratio (HR) with 95% confidence interval (CI) of the highest versus the lowest saturated fat intake from cohort studies were weighed by an inverse variance method to combine HRs.
RESULTS
Five studies of intracerebral hemorrhage and 11 studies/comparisons of ischemic stroke were selected. A meta-analysis of intracerebral hemorrhage excluding subarachnoid hemorrhage showed a strong inverse association in Japanese (n=3, HR=0.55, 95% CI 0.32-0.94) but not in non-Japanese (n=2, HR=0.98, 95% CI 0.62-1.53). A meta-analysis of ischemic stroke showed a mild inverse association in Japanese (n=4, HR=0.82, 95% CI 0.71-0.93) but not in non-Japanese (n=7, HR= 0.93, 95% CI 0.84-1.03). The effect size of saturated fat in reducing the risk of stroke in Japanese was stronger for intracerebral hemorrhage (45% reduction) than for ischemic stroke (18% reduction).
CONCLUSIONS
In Japanese but not in non-Japanese, a diet high in saturated fat is associated with a low risk of intracerebral hemorrhage and ischemic stroke. This may be due to differences in the range of intake of saturated fat, genetic susceptibility, incidence of lacunar infarction, and/or confounding factors such as dietary proteins. An intervention study targeting Japanese will be required to verify the causality.
Topics: Brain Ischemia; Cerebral Hemorrhage; Dietary Fats; Fatty Acids; Humans; Incidence; Japan; Prospective Studies; Risk Factors; Stroke
PubMed: 29269706
DOI: 10.5551/jat.41632 -
Lipids Oct 2010Dietary and policy recommendations frequently focus on reducing saturated fatty acid consumption for improving cardiometabolic health, based largely on ecologic and... (Review)
Review
Dietary and policy recommendations frequently focus on reducing saturated fatty acid consumption for improving cardiometabolic health, based largely on ecologic and animal studies. Recent advances in nutritional science now allow assessment of critical questions about health effects of saturated fatty acids (SFA). We reviewed the evidence from randomized controlled trials (RCTs) of lipid and non-lipid risk factors, prospective cohort studies of disease endpoints, and RCTs of disease endpoints for cardiometabolic effects of SFA consumption in humans, including whether effects vary depending on specific SFA chain-length; on the replacement nutrient; or on disease outcomes evaluated. Compared with carbohydrate, the TC:HDL-C ratio is nonsignificantly affected by consumption of myristic or palmitic acid, is nonsignificantly decreased by stearic acid, and is significantly decreased by lauric acid. However, insufficient evidence exists for different chain-length-specific effects on other risk pathways or, more importantly, disease endpoints. Based on consistent evidence from human studies, replacing SFA with polyunsaturated fat modestly lowers coronary heart disease risk, with ~10% risk reduction for a 5% energy substitution; whereas replacing SFA with carbohydrate has no benefit and replacing SFA with monounsaturated fat has uncertain effects. Evidence for the effects of SFA consumption on vascular function, insulin resistance, diabetes, and stroke is mixed, with many studies showing no clear effects, highlighting a need for further investigation of these endpoints. Public health emphasis on reducing SFA consumption without considering the replacement nutrient or, more importantly, the many other food-based risk factors for cardiometabolic disease is unlikely to produce substantial intended benefits.
Topics: Cardiovascular Diseases; Diabetes Mellitus; Dietary Fats; Fatty Acids; Humans; Public Health; Risk Factors; Stroke
PubMed: 20354806
DOI: 10.1007/s11745-010-3393-4 -
The American Journal of Clinical... Sep 2022Many studies have linked intakes of fat and of specific fatty acids during pregnancy with preeclampsia; however, information on the association of intake before...
BACKGROUND
Many studies have linked intakes of fat and of specific fatty acids during pregnancy with preeclampsia; however, information on the association of intake before pregnancy with hypertensive disorders of pregnancy (HDP) is scant.
OBJECTIVES
We evaluated the associations of intakes of major and specific types of fat before pregnancy with the risks of HDP, including preeclampsia and gestational hypertension (GHTN).
METHODS
We followed 11,535 women without chronic disease participating in the Nurses' Health Study II from 1991 and 2009. Pre-pregnancy dietary fat was assessed by an FFQ. Intakes of total fat, saturated fat, trans fatty acid (TFA), MUFAs, PUFAs, and fat subtypes (omega-3 and omega-6) were categorized into quintiles of intake. HDP were self-reported. The RRs (95% CIs) of HDP were estimated by log-binomial generalized estimating equation regression models, with an exchangeable correlation matrix to account for repeated pregnancies while adjusting for potential confounders.
RESULTS
During 19 years of follow-up, there were 495 cases of preeclampsia (2.9%) and 561 (3.3%) cases of GHTN in 16,892 singleton pregnancies. The mean age at pregnancy was 34.6 years (SD, 3.9 years). Among major fat types, only pre-pregnancy TFA was related to a higher risk of HDP (RR, 1.32; 95% CI: 1.05-1.66), and only for preeclampsia (RR, 1.50; 95% CI: 1.07-2.10) but not for GHTN (RR, 1.21; 95% CI: 0.87-1.70). Among specific types of PUFAs, intake of arachidonic acid was positively related with GHTN (RR, 1.43; 95% CI: 1.00-2.04) but not preeclampsia (RR, 1.08; 95% CI: 0.75-1.57). In analyses restricted to pregnancies 1 year after the diet assessment, women with the highest intake of long-chain omega-3 fatty acids had a 31% lower risk of HDP (95% CI: 3%-51%), which was driven by preeclampsia (RR, 0.55; 95% CI: 0.33-0.92).
CONCLUSIONS
Pre-pregnancy intakes of total fat, saturated fat, and MUFA were unrelated to HDP, whereas TFA was positively related to HDP. These findings highlight the importance of ongoing efforts to eliminate TFA from the global food supply.
Topics: Dietary Fats; Fatty Acids; Fatty Acids, Monounsaturated; Fatty Acids, Omega-3; Female; Humans; Hypertension, Pregnancy-Induced; Pre-Eclampsia; Pregnancy; Trans Fatty Acids
PubMed: 35575613
DOI: 10.1093/ajcn/nqac145