Replacement Of Dietary Saturated Fat Research Articles

Determination of variability in serum low density lipoprotein cholesterol response to the replacement of dietary saturated fat with unsaturated fat, in the Reading, Imperial, Surrey Saturated fat Cholesterol Intervention (‘RISSCI’) project

Determination of variability in serum low density lipoprotein cholesterol response to the replacement of dietary saturated fat with unsaturated fat, in the Reading, Imperial, Surrey Saturated fat Cholesterol Intervention (‘RISSCI’) project - Volume 79 Issue OCE1

Dietary and Pharmacological Fatty Acids and Cardiovascular Health.

The effects of dietary intake of different fatty acids and pharmacological use of fatty acids, specifically long-chain n-3 polyunsaturated fatty acids (LC n-3 PUFAs), on cardiovascular health and atherosclerotic cardiovascular disease (ASCVD) prevention have been examined in a large number of observational studies and clinical trials. This review summarizes recent data and discusses potential mechanisms. The review is based on the authors' knowledge of the field supplemented by a PubMed search using the terms seafood, fish oil, saturated fatty acids, omega-3 fatty acids, eicosapentaenoic acid, docosahexaenoic acid, polyunsaturated fatty acids, monounsaturated fatty acids, and ASCVD. We mainly discuss the recent clinical trials that examine the effects of different types of dietary fatty acids and pharmacological use of n-3 PUFA products on ASCVD prevention and the potential mechanisms. While replacement of dietary saturated fat with unsaturated fat, polyunsaturated fat in particular, or intake of LC n-3 PUFA-rich seafood has generally shown benefit for ASCVD prevention and is recommended for cardiovascular benefits, data on effects of n-3 PUFA products on ASCVD health are inconsistent. However, recent clinical trials support benefits of prescription EPA in ASCVD prevention. n-3 PUFAs may contribute to ASCVD prevention through multiple mechanisms, including lowering plasma triglyceride levels, anti-inflammatory effects, antithrombotic effects, and effects on endothelial function.

Replacement of dietary saturated fat with unsaturated fats increases numbers of circulating endothelial progenitor cells and decreases numbers of microparticles: findings from the randomized, controlled Dietary Intervention and VAScular function (DIVAS) study

Endothelial progenitor cells (EPCs) and microparticles are emerging as novel markers of cardiovascular disease (CVD) risk, which could potentially be modified by dietary fat. We have previously shown that replacing dietary saturated fatty acids (SFAs) with monounsaturated or n-6 (ω-6) polyunsaturated fatty acids (MUFAs or PUFAs, respectively) improved lipid biomarkers, blood pressure, and markers of endothelial activation, but their effects on circulating EPCs and microparticles are unclear. The Dietary Intervention and VAScular function (DIVAS) Study investigated the replacement of 9.5-9.6% of total energy (%TE) contributed by SFAs with MUFAs or n-6 PUFAs for 16 wk on EPC and microparticle numbers in United Kingdom adults with moderate CVD risk. In this randomized, controlled, single-blind, parallel-group dietary intervention, men and women aged 21-60 y (n=190) with moderate CVD risk (≥50% above the population mean) consumed 1 of three 16-wk isoenergetic diets. Target compositions for total fat, SFAs, MUFAs, and n-6 PUFAs (%TE) were as follows: SFA-rich diet (36:17:11:4; n=64), MUFA-rich diet (36:9:19:4; n=62), and n-6 PUFA-rich diet (36:9:13:10; n=66). Circulating EPC, endothelial microparticle (EMP), and platelet microparticle (PMP) numbers were analyzed by flow cytometry. Dietary intake, vascular function, and other cardiometabolic risk factors were determined at baseline. Relative to the SFA-rich diet, MUFA- and n-6 PUFA-rich diets decreased EMP (-47.3%, -44.9%) respectively and PMP (-36.8%, -39.1%) numbers (overall diet effects, P<0.01). The MUFA-rich diet increased EPC numbers (+28.4%; P=0.023). Additional analyses that used stepwise regression models identified the augmentation index (measuring arterial stiffness determined by pulse-wave analysis) as an independent predictor of baseline EPC and microparticle numbers. Replacement of 9.5-9.6%TE dietary SFAs with MUFAs increased EPC numbers, and replacement with either MUFAs or n-6 PUFAs decreased microparticle numbers, suggesting beneficial effects on endothelial repair and maintenance. Further studies are warranted to determine the mechanisms underlying the favorable effects on EPC and microparticle numbers after SFA replacement. This trial was registered at www.clinicaltrials.gov as NCT01478958.

Replacement of Dietary Saturated Fat by PUFA-Rich Pumpkin Seed Oil Attenuates Non-Alcoholic Fatty Liver Disease and Atherosclerosis Development, with Additional Health Effects of Virgin over Refined Oil.

Background and AimsAs dietary saturated fatty acids are associated with metabolic and cardiovascular disease, a potentially interesting strategy to reduce disease risk is modification of the quality of fat consumed. Vegetable oils represent an attractive target for intervention, as they largely determine the intake of dietary fats. Furthermore, besides potential health effects conferred by the type of fatty acids in a vegetable oil, other minor components (e.g. phytochemicals) may also have health benefits. Here, we investigated the potential long-term health effects of isocaloric substitution of dietary fat (i.e. partial replacement of saturated by unsaturated fats), as well as putative additional effects of phytochemicals present in unrefined (virgin) oil on development of non-alcoholic fatty liver disease (NAFLD) and associated atherosclerosis. For this, we used pumpkin seed oil, because it is high in unsaturated fatty acids and a rich source of phytochemicals.MethodsApoE*3Leiden mice were fed a Western-type diet (CON) containing cocoa butter (15% w/w) and cholesterol (1% w/w) for 20 weeks to induce risk factors and disease endpoints. In separate groups, cocoa butter was replaced by refined (REF) or virgin (VIR) pumpkin seed oil (comparable in fatty acid composition, but different in phytochemical content).ResultsBoth oils improved dyslipidaemia, with decreased (V)LDL-cholesterol and triglyceride levels in comparison with CON, and additional cholesterol-lowering effects of VIR over REF. While REF did not affect plasma inflammatory markers, VIR reduced circulating serum amyloid A and soluble vascular adhesion molecule-1. NAFLD and atherosclerosis development was modestly reduced in REF, and VIR strongly decreased liver steatosis and inflammation as well as atherosclerotic lesion area and severity.ConclusionsOverall, we show that an isocaloric switch from a diet rich in saturated fat to a diet rich in unsaturated fat can attenuate NAFLD and atherosclerosis development. Phytochemical-rich virgin pumpkin seed oil exerts additional anti-inflammatory effects resulting in more pronounced health effects.

Dietary fat modification in patients with chronic kidney disease: n-3 fatty acids and beyond

Replacement of dietary saturated fat with unsaturated fat has been recommended for prevention of cardiovascular disease (CVD) in the general population. Less is known of the health risks in individuals with chronic kidney disease (CKD), of a diet with an unhealthy fat profile, in general characterized by insufficient polyunsaturated fatty acids (PUFA) and excess satu-rated fatty acids (SFA). The dietary intake of PUFA, both the n-3 and n-6 subfamilies, is increasingly gaining attention in CKD, owing to its broad cardioprotective effects. Conversely, dietary SFA may promote CVD in this vulnerable population. This review discusses the potential benefits of dietary fat modification in CKD patients, including plausible effects on renal function, albuminuria, lipoproteins, nutritional status, inflammation, thrombosis and clinical outcomes. Increasing evidence supports the concept that n-3 PUFA might have therapeutic potential in reducing proteinuria in CKD and reducing triglycerides and inflammation in dialysis patients. In addition, emerging evidence suggests that linoleic acid, a major n-6 PUFA derived from vegetable oils, may be beneficial for a number of CVD risk factors. Increased consumption of oily fish as part of plant-based diets with low content of SFA is likely to benefit patients who have CKD, or are at risk of developing CKD. Such recommendations are in line with the concept of a healthy "Mediterranean diet" and are in line with current dietary recommendations for CVD prevention in the community.

Replacement of dietary saturated fat with trans fat reduces serum paraoxonase activity in healthy men and women

Replacement of dietary saturated fat with trans fat reduces serum paraoxonase activity in healthy men and women

Supplementation of postmenopausal women with fish oil does not increase overall oxidation of LDL ex vivo compared to dietary oils rich in oleate and linoleate

Although replacement of dietary saturated fat with monounsaturated and polyunsaturated fatty acids (MUFA and PUFA) has been advocated for the reduction of cardiovascular disease risk, diets high in PUFA could increase low density lipoprotein (LDL) susceptibility to oxidation, potentially contributing to the pathology of atherosclerosis. To investigate this possibility, 15 postmenopausal women in a blinded crossover trial consumed 15 g of sunflower oil (SU) providing 12.3 g/day of oleate, safflower oil (SA) providing 10.5 g/day of linoleate, and fish oil (FO) providing 2.0 g/day of eicosapentaenoate (EPA) and 1.4 g/day of docosahexaenoate (DHA). During CuSO4-mediated oxidation, LDL was depleted of α-tocopherol more rapidly after FO supplementation than after supplementation with SU (P = 0.0001) and SA (P = 0.05). In LDL phospholipid and cholesteryl ester fractions, loss of n-3 PUFA was greater and loss of n-6 PUFA less after FO supplementation than after SU and SA supplementation (P < 0.05 for all), but loss of total PUFA did not differ. The lag phase for phosphatidylcholine hydroperoxide (PCOOH) formation was shorter after FO supplementation than after supplementation with SU (P = 0.0001) and SA (P = 0.006), whereas the lag phase for cholesteryl linoleate hydroperoxide (CE18:2OOH) formation was shorter after FO supplementation than after SU (P = 0.03) but not SA. In contrast, maximal rates of PCOOH and CE18:2OOH formation were lower after FO supplementation than after SA (P = 0.02 and 0.0001, respectively) and maximal concentrations of PCOOH and CE18:2OOH were lower after FO supplementation than after SA (P = 0.03 and 0.0006, respectively). Taken together, our results suggest that FO supplementation does not increase the overall oxidation of LDL ex vivo, especially when compared with SA supplementation. Consequently, health benefits related to increased fish consumption may not be offset by increased LDL oxidative susceptibility. —Higdon, J. V., S. H. Du, Y. S. Lee, T. Wu, and R. C. Wander. Supplementation of postmenopausal women with fish oil does not increase overall oxidation of LDL ex vivo compared to dietary oils rich in oleate and linoleate.

Supplementation of postmenopausal women with fish oil rich in eicosapentaenoic acid and docosahexaenoic acid is not associated with greater in vivo lipid peroxidation compared with oils rich in oleate and linoleate as assessed by plasma malondialdehyde and F2-isoprostanes

Although the replacement of dietary saturated fat with unsaturated fat has been advocated to reduce the risk of cardiovascular disease, diets high in polyunsaturated fatty acids (PUFAs) could increase lipid peroxidation, potentially contributing to the pathology of atherosclerosis. The objective of this study was to examine indexes of in vivo lipid peroxidation, including free F(2)-isoprostanes, malondialdehyde (MDA), and thiobarbituric acid reacting substances (TBARS), in the plasma of postmenopausal women taking dietary oil supplements rich in oleate, linoleate, and both eicosapentaenoic acid and docosahexaenoic acid. Fifteen postmenopausal women took 15 g sunflower oil/d, providing 12.3 g oleate/d; safflower oil, providing 10.5 g linoleate/d; and fish oil, providing 2.0 g EPA/d and 1.4 g DHA/d in a 3-treatment crossover trial. Plasma free F(2)-isoprostane concentrations were lower after fish-oil supplementation than after sunflower-oil supplementation (P: = 0.003). When plasma free F(2)-isoprostane concentrations were normalized to plasma arachidonic acid concentrations, significant differences among the supplements were eliminated. Plasma MDA concentrations were lower after fish-oil supplementation than after sunflower-oil supplementation (P: = 0.04), whereas plasma TBARS were higher after fish-oil supplementation than after sunflower oil (P: = 0.003) and safflower oil (P: = 0.001) supplementation. When plasma MDA concentrations were normalized to plasma PUFA concentrations, significant differences were eliminated, but TBARS remained higher after fish-oil supplementation than after sunflower oil (P: = 0.01) and safflower-oil (P: = 0.0003) supplementation. With fish-oil supplementation, there was no evidence of increased lipid peroxidation when assessed by plasma F(2)-isoprostanes and MDA, although plasma TBARS was higher than with sunflower-oil and safflower-oil supplementation.

Replacement of dietary saturated fat with monounsaturated fat: effect on atherogenesis in cholesterol-fed rabbits clamped at the same plasma cholesterol level

The aim was to compare the effect on atherogenesis of dietary monounsaturated and saturated fatty acids in cholesterol-clamped rabbits. To obtain an average plasma cholesterol concentration of 20 mmol/l in each rabbit during the 13-week cholesterol-feeding period, dietary cholesterol was adjusted weekly. The amount of fat fed daily was 10 g per rabbit in Expts A (n 23), C (n 36), and D (n 58) and 5 g per rabbit in Expt B (n 24). The source of monounsaturated fatty acids was olive oil in all four experiments. The source of saturated fatty acids was butter in Expt A, lard in Expt B, coconut oil in Expt C, and butter or lard in Expt D. Generally, olive oil-fed groups received more cholesterol and tended to have more cholesterol in VLDL and less in LDL compared with groups receiving saturated fat. Analysis of variance of the combined results of all four experiments showed that, in comparison with saturated fat, olive oil lowered aortic cholesterol by 13 (-9-30, 95% confidence interval) % in the aortic arch, and by 10 (-10-26) % in the thoracic aorta, which was not significant. In the comparison with olive oil, no differences in effects on aortic cholesterol content were detected between butter, lard and coconut oil. These findings do not support the view that replacement of dietary saturated fat with olive oil has a major impact on the development of atherosclerosis in addition to that accounted for by changes in plasma cholesterol levels.

Replacement of dietary saturated fat with monounsaturated fat: effect on atherogenesis in cholesterol-fed rabbits clamped at the same plasma cholesterol level

Replacement of dietary saturated fat with monounsaturated fat: effect on atherogenesis in cholesterol-fed rabbits clamped at the same plasma cholesterol level

Modification of human platelet function by a diet enriched in saturated or polyunsaturated fat

Twelve healthy male subjects were maintained on a saturated fat (SF) dietary regimen followed by a polyunsaturated fat (PUF) regimen. At selected intervals a number of tests were carried out to assess the effect of SF or PUF on platelet composition and activation. Concomitant with the fall in serum cholesterol, associated with the PUF diet, there was a decrease in plasma heparin neutralizing activity (as measured by the heparin-thrombin clotting time), and a fall in the number of circulating platelet aggregates was also observed. These two parameters suggest diminished platelet activation. Malondialdehyde production (an index of prostaglandin synthesis) was unchanged throughout the two dietary periods. Changes in the quality of the dietary fat were manifested in the phospholipid fraction of platelet lipids, particularly phosphatidyl choline and sphingomyelin. Platelet counts of whole blood were significantly decreased when subjects were consuming PUF, but not all of these alterations were reflected in platelet-rich plasma. These results indicate that platelets may be activated in apparently normal people consuming a SF diet (the standard diet of developed countries) and that this activation may be decreased by replacement of dietary SF with PUF.