Meta-analysis of the effects of quinoa (Chenopodium quinoa) interventions on blood lipids

Objective: The purpose of the current study is to conduct a meta-analysis of published randomized controlled trials to explore the quantitative effect of quinoa supplementation on serum lipid concentrations. Methods: Online databases, including Web of Science, Scopus, and PubMed, were systematically searched. A comprehensive literature review was performed based on English reports of randomized controlled trials of quinoa on lipid profiles in adults, which were published up to July 2020. Weighted mean differences (WMD) with a 95% confidence interval (CI) were assigned as the ultimate effects of using random models. Study quality was assessed by using the Cochran score, and a meta-analysis was conducted. Results: Five RCTs with eight intervention arms, including 291 participants, were selected for the present meta-analysis. The intervention period was between 4 and 12 weeks. The results showed doses higher than 50 g of quinoa consumption and duration more than six weeks of intervention significantly reduced serum triglyceride (TG) levels (WMD: -0.864 mg/dl; 95% CI: -1.286, -0.442, P < 0.001) and (WMD: -0.623 mg/dl; 95% CI: -1.015, -0.232, P = 0.002), respectively. In general, quinoa supplementation did not have a significant effect on concentrations of high-density lipoprotein cholesterol (HDL-C) levels (WMD: -0.145 mg/dl; 95% CI: -0.377, 0.086, P = 0.218), low-density lipoprotein cholesterol (LDL-C) levels, (WMD: 0.082 mg/dl; 95% CI: -0.150, 0.314, P = 0.489), and total cholesterol (TC) levels)WMD: -0.036 mg/dl; 95% CI: -0.267, 0.195, P = 0.759(. Conclusion: This study reveals quinoa supplementation in doses higher than 50 g/day and the duration more than six weeks significantly reduced TG levels. However, further studies in this area are recommended to understand the potential mechanisms of quinoa on blood lipids.