Combining Plant Sterols With Walking Lowers Postprandial Triacylglycerol More Than Walking Only in Chinese Men With Elevated Body Mass Index

Effects of phytosterols on cardiovascular risk factors: A systematic review and meta-analysis of randomized controlled trials

Cardiovascular diseases are the major cause of death globally. The primary risk factors are high blood lipid levels, hypertension, diabetes, and obesity. Phytosterols are naturally occurring plant bioactive substances. Short-term clinical trials have demonstrated phytosterols' cholesterol-lowering potential, but their effects on cardiovascular risk factors remain controversial, and relevant meta-analyses are limited and incomplete. We conducted a systematic and comprehensive search of PubMed, Web of Science, Embase and Cochrane Library up to December 22, 2023. A total of 109 randomized controlled trials (RCTS) of phytosterols (PS) intervention on cardiovascular risk factor outcomes were included in a preliminary screening of the retrieved literature by Endnote 20. We assessed the quality of all included randomized controlled trials using the Cochrane Collaboration's Risk of Bias tool. Cochrane data conversion tool was used for data conversion, and finally Stata was used for meta-analysis, egger test and sensitivity analysis of the included studies. The results indicated that dietary phytosterols intake could significantly decrease total cholesterol (TC) level (mean difference = -13.41; 95% confidence interval [CI]: -15.19, -11.63, p < 0.001), low density lipoprotein cholesterol (LDL-C) level (mean difference = -12.57; 95% CI: -13.87, -11.26, p < 0.001), triglycerides (TG) level (mean difference = -6.34; 95% CI: -9.43, -3.25, p < 0.001), C-reactive protein (CRP) level (mean difference = -0.05; 95% CI: -0.08, -0.01, p = 0.671), systolic blood pressure (SBP) level (mean difference = -2.10; 95% CI: -3.27, -0.9, p < 0.001), diastolic blood pressure (DBP) level (mean difference = -0.83; 95% CI: -0.58, -0.07, p = 0.032), increased high-density lipoprotein cholesterol (HDL-C) level (mean difference = 0.46; 95% CI: 0.13, 0.78, p = 0.005), but did not alter the levels of blood glucose (GLU) (mean difference = -0.44; 95% CI: -1.64, 0.76, p = 0.471), glycosylated hemoglobin, Type A1C (HbA1c) (mean difference = -0.28; 95% CI: -0.75, 0.20, p = 0.251), interleukin-6 (IL-6) (mean difference = 0.00; 95% CI: -0.02, 0.02, p = 0.980), tumor necrosis factor (TNF-α) (mean difference = 0.08; 95% CI: -0.08, 0.24, p = 0.335), oxidized low-density lipoprotein cholesterol (OXLDL-C) (standard mean difference = 0.16; 95% CI: -0.38, 0.06, p = 0.154), body mass index (BMI) (mean difference = 0.01; 95% CI: -0.07, 0.09, p = 0.886), waist circumference (WC) (mean difference = -0.10; 95% CI: -0.50, 0.30, p = 0.625) and body weight (mean difference = 0.03; 95% CI: -0.18, 0.24, p = 0.787). Our results suggest that phytosterols may be beneficial in reducing the levels of TC, LDL-C, TG, CRP, SBP, and DBP, but have no significant effect on GLU, HbA1c, TNF-α, IL-6, OXLDL-C, BMI, WC, and Weight. However, there were a small number of RCTS included in this study and their small population size may have reduced the quality of the study. And most of the included studies were short-term intervention trials. Therefore, higher quality studies need to be designed in future studies to establish more accurate conclusions.

Phytosterol supplementation in capsules or tablets as adjunctive treatment for hypercholesterolemia: A systematic review of randomized controlled trials

BACKGROUND

The exploration of lipid-lowering resources, such as phytosterols, for the complementary nutritional treatment of hypercholesterolemia is relevant to reduce cardiovascular risk. The use of phytosterols in capsules or tablets can bring advantages in the context of diet therapy, but such format is still less studied when compared to fortified foods.

OBJECTIVE

Systematically review randomized clinical trials on the effects of phytosterol supplementation, in capsules or tablets, on the lipid profile and its use in the treatment of hypercholesterolemia in adults.

DESIGN

A systematic review was carried out in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analysis, with a PROSPERO protocol registered under number CRD42021249539. The process was conducted by two independent reviewers. Only randomized clinical trials with phytosterol supplementation in adult individuals with hypercholesterolemia were included. The terms were searched in the databases: PubMed/MEDLINE, Cochrane Library/CENTRAL, Embase, LILACS and Web of Science, without restriction of time and language. The manual search was also performed through the list of references of articles included in this review.

RESULTS

The searches resulted in 977 articles. 22 articles were selected, whose full text was read, and according to the eligibility criteria 10 were incorporated into the review. The studies were separated into groups according to the association of the intervention with changes in lifestyle and the characteristics extracted from the studies were summarized and displayed in tables. Most studies have revealed a positive association between phytosterol supplementation and cholesterol reduction, despite the short duration of interventions.

CONCLUSION

The analyzed studies showed that phytosterol supplements can be useful to modulate the lipid profile, helping to reduce the plasma concentration of LDL cholesterol. However, more research with the aforementioned supplementation in such pharmaceutical formats should be encouraged.

Effect of Prior Exercise on Postprandial Lipemia: An Updated Meta-Analysis and Systematic Review

The purpose of this systematic review was to synthesize the results from current literature examining the effects of prior exercise on the postprandial triglyceride (TG) response to evaluate current literature and provide future direction. A quantitative review was performed using meta-analytic methods to quantify individual effect sizes. A moderator analysis was performed to investigate potential variables that could influence the effect of prior exercise on postprandial TG response. Two hundred and seventy-nine effects were retrieved from 165 studies for the total TG response and 142 effects from 87 studies for the incremental area under the curve TG response. There was a moderate effect of exercise on the total TG response (Cohen's d = -0.47; p < .0001). Moderator analysis revealed exercise energy expenditure significantly moderated the effect of prior exercise on the total TG response (p < .0001). Exercise modality (e.g., cardiovascular, resistance, combination of both cardiovascular and resistance, or standing), cardiovascular exercise type (e.g., continuous, interval, concurrent, or combined), and timing of exercise prior to meal administration significantly affected the total TG response (p < .001). Additionally, exercise had a moderate effect on the incremental area under the curve TG response (Cohen's d = -0.40; p < .0001). The current analysis reveals a more homogeneous data set than previously reported. The attenuation of postprandial TG appears largely dependent on exercise energy expenditure (∼2 MJ) and the timing of exercise. The effect of prior exercise on the postprandial TG response appears to be transient; therefore, exercise should be frequent to elicit an adaptation.

Postprandial Metabolism and Physical Activity in Asians: A Narrative Review

The widespread benefits of physical activity in enhancing health and lowering the risk of non-communicable chronic diseases are well established across populations globally. Nevertheless, the prevalence of several lifestyle-related chronic diseases, including cardiovascular disease, varies markedly across countries and ethnicities. Direct ethnic comparative studies on the health benefits of physical activity are sparse and evidence-based physical activity guidelines are not ethnicity-specific. Indeed, physical activity guidelines in some Asian countries were developed primarily based on data from Western populations even though the magnitude of potential benefit may not be the same among different ethnic groups. Unfavorable diurnal perturbations in postprandial triglycerides and glucose are risk factors for cardiovascular disease. This narrative review summarizes differences in these risk factors primarily between individuals of Asian and white European descent but also within different Asian groups. Moreover, the variable effects of physical activity on mitigating risk factors among these ethnic groups are highlighted along with the underlying metabolic and hormonal factors that potentially account for these differences. Future ethnic comparative studies should include investigations in understudied ethnic groups, such as those of East Asian origin, given that the effectiveness of physical activity for ameliorating cardiovascular disease varies even among Asian groups.

Effects of a single bout of walking on postprandial triglycerides in men of Chinese, European and Japanese descent: a multisite randomised crossover trial

Introduction

Elevated non-fasting triglyceride (TG) concentrations are a risk factor for cardiovascular diseases but can be reduced after acute exercise. Ethnic-based differences in the magnitude of postprandial lipaemia and the extent that acute exercise reduces postprandial TG are poorly characterised across some ethnicities including those of East Asian origin. This paper describes the protocol of a multisite randomised crossover study comparing the effect of acute walking on postprandial TG in two groups of East Asian men with European men.

Methods and analysis

Twenty Japanese, 20 Singaporean Chinese and 20 white British healthy men (21–39 years) recruited from Japan, Singapore and the UK, respectively, will complete two, 2-day trials. Fasted and postprandial venous blood samples and arterial blood pressure measurements will be taken over 6 hours the day after either: (1) 60-min treadmill walking; or (2) a rest day of normal living. The primary outcome is the difference in postprandial TG among ethnic groups after rest and walking. Secondary outcomes include cholesterol, glucose, insulin, ketone bodies, preheparin lipoprotein lipase, C-reactive protein and systolic/diastolic blood pressure.

Ethics and dissemination

The study was approved by the Ethics Review Committee on Research with Human Subjects of Waseda University and the Nanyang Technological University Institutional Review Board. Relevant approval will be obtained from the UK site. Research findings will be disseminated through peer-reviewed journal publication and health conferences.

Trial registration number

UMIN000038625.