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Objective: To determine the effect of diets low in saturated fatty acids and high in monounsaturated fatty acids (MUFA) or polyunsaturated fatty acids on body composition in participants at risk for metabolic syndrome (MetS).Methods: This study was a randomized, crossover, controlled feeding study. Participants (n = 101, ages 49.5 ± 1.2, BMI 29.4 ± 0.4 kg/m2 ) were randomized to five isocaloric diets containing treatment oils: Canola, CanolaOleic, CanolaDHA, Corn/Safflower, and Flax/Safflower. Each diet period was 4 weeks followed by a 2- to 4-week washout period.Results: Canola (3.1 kg, P = 0.026) and CanolaOleic oil diets (3.09 kg, P = 0.03) reduced android fat mass compared with the Flax/Saff oil diet (3.2 kg), particularly in men. The decrease in abdominal fat mass was correlated with the reduction in blood pressure after the Canola (systolic blood pressure: r = 0.26, P = 0.062; diastolic blood pressure: r = 0.38, P = 0.0049) and CanolaOleic oil diets (systolic blood pressure: r = 0.39 P = 0.004; diastolic blood pressure: r = 0.45, P = 0.0006). The decrease in abdominal fat mass also was associated with a reduction in triglyceride levels after the CanolaOleic oil diet (r = 0.42, P = 0.002).Conclusions: Diets high in MUFA (compared with PUFA) reduced central obesity with an accompanying improvement in MetS risk factors. Diets high in MUFA may be beneficial for treating and perhaps preventing MetS. [ABSTRACT FROM AUTHOR]

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Background In addition to lowering LDL-C, emerging data suggests that phytosterols (PS) may reduce blood triglycerides (TG), however, the underlying mechanisms are not known. Methods We examined the TG-lowering mechanisms of dietary PS in Syrian golden hamsters randomly assigned to a high fat (HF) diet or the HF diet supplemented with PS (2%) for 6 weeks (n = 12/group). An additional subset of animals (n = 12) was provided the HF diet supplemented with ezetimibe (EZ, 0.002%) as a positive control as it is a cholesterollowering agent with known TG-lowering properties. Results In confirmation of diet formulation and compound delivery, both the PS and EZ treatments lowered (p < 0.05) intestinal cholesterol absorption (24 and 31%, respectively), blood non- HDL cholesterol (61 and 66%, respectively), and hepatic cholesterol (45 and 55%, respectively) compared with the HF-fed animals. Blood TG concentrations were lower (p < 0.05) in the PS (49%) and EZ (68%)-treated animals compared with the HF group. The TGlowering response in the PS-supplemented group was associated with reduced (p < 0.05) intestinal SREBP1c mRNA (0.45 fold of HF), hepatic PPARα mRNA (0.73 fold of HF), hepatic FAS protein abundance (0.68 fold of HD), and de novo lipogenesis (44%) compared with the HF group. Similarly, lipogenesis was lower in the EZ-treated animals, albeit through a reduction in the hepatic protein abundance of ACC (0.47 fold of HF). Conclusions Study results suggest that dietary PS are protective against diet-induced hypertriglyceridemia, likely through multiple mechanisms that involve modulation of intestinal fatty acid metabolism and a reduction in hepatic lipogenesis. [ABSTRACT FROM AUTHOR]

Effects of dietary fibers on human postprandial energetics remain undefined. The objective of the present study was to explore effects of whole yellow pea flour (WPF) and fractionated pea flour (FPF) on postprandial energy expenditure, substrate utilization, and hepatic triglyceride synthesis rate. Using a crossover-diet controlled design, 23 overweight men and women received muffins containing WPF, FPF, and white wheat flour (WF) for 28 days, followed by 28-day washout periods. Subjects received 50 g/day WPF and WF. Given that FPF is approximately 84% fiber, the amount of FPF administered to volunteers was equivalent to the amount of pea-derived fiber in the WPF treatment. Four weeks of FPF consumption reduced ( P=.007) total postprandial energy expenditure (333.0±3.6 kcal/330 minutes) compared with WF (349.3±3.6 kcal/330 minutes). When values were normalized to the level of food energy consumed, FPF (4.6±0.3%) decreased ( P=.018) the thermic effect of food (TEF) compared with WF (5.7±0.3%). Carbohydrate oxidation tended to be lower ( P=.075) with FPF (44.7±2.1 g/330 minutes) versus WF (51.2±0.1.9 g/330 minutes). WPF had no effect on total energy expenditure, TEF, or carbohydrate oxidation. Only after 370 minutes was cumulative oxidation of [1-13C]palmitic acid higher ( P=.045) in the WPF group (0.96±0.05%) compared with FPF (0.81±0.05%). Neither treatment had any effect on hepatic triglyceride synthesis rate. In conclusion, chronic ingestion of different fractions of yellow peas imposes distinctive effects on postprandial energy expenditure and substrate utilization. [ABSTRACT FROM AUTHOR]

Abstract: Phytosterols (PSs) have been recently added to various mediums. Nevertheless, matrices with functional properties, such as medium-chain triglycerides (MCTs), should be precisely examined for supplementary advantages. The objective of this study was to identify the existence of combined biological actions of a functional oil enriched in PSs within MCTs and high-oleic canola (HOC), relative to a control (olive oil), in overweight, hyperlipidemic men using a rigorously controlled dietary intervention. Twenty-three overweight, hyperlipidemic men consumed both types of oil in a randomized, crossover trial for 6 weeks each. Fasted plasma samples were collected on the first and last 2 days of each study period. Body weight decreased −1.22 ± 0.35 kg (P = .0019) and −1.68 ± 0.47 kg (P = .0016) after the 6-week study period in the olive oil and functional oil groups, respectively. The end points for total cholesterol and low-density lipoprotein cholesterol (LDL-C) in the functional oil group (P = .0006) were lower than in the olive oil group (P = .0002). Total cholesterol values decreased from comparable baseline to end point of 4.71 ± 0.16 mmol/L (P < .0001) in the functional oil phase and 5.14 ± 0.19 mmol/L (P = .0001) in the olive oil phase (P = .0592). In addition, LDL-C demonstrated a similar drop, to an end point of 3.12 ± 0.16 mmol/L (P < .0001) and 3.54 ± 0.18 mmol/L (P = .0002), for the functional oil and olive oil groups, respectively, with significant changes (P = .0221). High-density lipoprotein cholesterol levels did not change in either treatment. Triacylglycerol end points decreased in functional oil and olive oil groups (P = .0195 and .0105, respectively) to the same extent from baseline. Results indicate that PSs mixed within an MCT- and HOC-rich matrix lower plasma LDL-C, without significantly changing the high-density lipoprotein cholesterol concentrations, in hyperlipidemic, overweight men, and may therefore decrease the risk of cardiovascular events. [Copyright &y& Elsevier]

The extent to which sterols and stanols modulate LDL particle size is unknown. We examined the effects of supplementation with unesterified plant sterols and stanols on several LDL electrophoretic characteristics. Healthy hypercholesterolemic subjects (n = 14) consumed each of four experimental diets contained plant sterols (S), plant stanols (SN), a 50:50 mixture of sterols and stanols (SSN), or cornstarch (control) in a randomized crossover design. The butter component of the diet was blended with unesterified sterols and stanols at a dose of 1.8 g/d. The LDL particles were characterized by polyacrylamide gradient gel electrophoresis of whole plasma. LDL cholesterol (LDL-C) concentrations decreased by 8.8, 13.6, and 13.1% in the S, SN, and SSN groups, respectively (P < 0.01) with a significant increase of 4.3% in the control group. None of the treatments with sterols and stanols induced significant changes in LDL peak particle diameter or in the cholesterol levels of the small LDL subfraction (<25.5 nm). The reduction in plasma LDL-C levels with SN consumption was due mainly to a decrease (P < 0.05) in the concentration of cholesterol in the large subfraction (>26.0 nm). The significant reduction in plasma LDL-C concentrations by sterol and stanol consumption in subjects was not paralleled by any beneficial changes in LDL electrophoretic characteristics. [ABSTRACT FROM AUTHOR]

Medium-chain triglycerides (MCT) have been proposed as weight-lowering agents, although there is some concern regarding their hyperlipidemic effect. This study evaluates the effects of a combination of MCT oil, phytosterols and flaxseed oil [functional oil (FctO)] on plasma lipid concentrations and LDL particle size. Twenty-four healthy overweight men (body mass index 28.2 +/- 0.4 kg/m(2)) consumed controlled diets designed to maintain weight for two periods of 29 d each. Diets contained 40% of energy as fat, 75% of which was added fat, either FctO or olive oil (OL). Body composition and blood samples were analyzed at the baseline and the endpoint of each period. Total cholesterol concentration decreased 12.5% (-0.68 mmol/L; P < 0.05) when subjects consumed FctO and 4.7% when they consumed OL. Similarly, FctO consumption lowered LDL cholesterol concentrations by 13.9%, whereas OL consumption did not. There was no difference in absolute change in LDL-cholesterol between FctO and OL consumption. Peak LDL particle size was greater in those who consumed FctO than in those who consumed OL (P < 0.05), with no effect of diet on proportion of large, medium or small particles. We conclude that those who consume a diet containing FctO have a better lipid profile than those who consume a diet rich in OL, which also leads to a larger lipoprotein particle size. Functional oil consumption can therefore help reduce the risk of cardiovascular disease. [ABSTRACT FROM AUTHOR]

Examines the potential effect of medium-chain triglycerides (MCT) as an agent in treating human obesity. Oxidation of medium chain fatty acids in the liver; Impact of MCT on human energy metabolism and satiety; Differences in the thermic response between lean and obese men.

Abstract: Objective: The aim of this study was to investigate the cholesterol-lowering mechanisms of corn fiber oil (CFO), ferulate phytostanyl esters (FPEs) and parent compounds of FPE, including sitostanol and ferulic acid, in hamsters. Method: Seventy male Golden Syrian hamsters were randomly assigned to six experimental diets for 4 weeks: (1) cornstarch–casein–sucrose-based control diet (control); and (2) control diet plus 0.1% (wt/wt) cholesterol (cholesterol–control). The remaining four groups were given cholesterol–control diet with: (3) 10% (wt/wt) CFO; (4) 0.5% (wt/wt) sitostanol; (5) 0.23% (wt/wt) ferulic acid; and (6) 0.73% (wt/wt) FPE. At the end of dietary intervention, total plasma cholesterol, high-density lipoprotein cholesterol and triglyceride concentrations were determined. Parameters of cholesterol kinetics, including cholesterol absorption and synthesis, as well as mRNA expression of sterol transporters such as Niemann–Pick C1 like 1 (NPC1L1), ATP-binding cassette G5 (ABCG5) and ABCG8, were assessed. Results: Supplementation with CFO decreased (P<.0001) plasma total cholesterol levels by 29% as compared with the cholesterol–control group, while FPE and sitostanol reduced (P<.02) cholesterolemia by 15% and 14%, respectively. CFO and sitostanol decreased (P<.05) cholesterol absorption by 24% compared to the cholesterol–control group. Dietary intervention did not alter the intestinal gene expression of ABCG5, ABCG8 and NPC1L1. Conclusion: The present results show that the CFO-induced and sitostanol-induced decrease in cholesterol absorption is independent of intestinal enterocyte sterol transporters such as ABCG5, ABCG8 and NPC1L1 in hamsters. [Copyright &y& Elsevier]