AUTHOR=Jiang Zhonghui , Qu Hua , Lin Gongyu , Shi Dazhuo , Chen Keji , Gao Zhuye TITLE=Lipid-Lowering Efficacy of the Capsaicin in Patients With Metabolic Syndrome: A Systematic Review and Meta-Analysis of Randomized Controlled Trials JOURNAL=Frontiers in Nutrition VOLUME=9 YEAR=2022 URL=https://www.frontiersin.org/journals/nutrition/articles/10.3389/fnut.2022.812294 DOI=10.3389/fnut.2022.812294 ISSN=2296-861X ABSTRACT=Background

Patients with metabolic syndrome (MetS) have increased cardiovascular risk. Capsaicin (CAP) has been shown to reduce lipids, but efficacy for patients with MetS is unknown.

Methods

A systematic review was performed according to PRISMA guidelines, to compare the effects of CAP against a placebo. Differences in the weight mean difference (WMD) with 95% confidence intervals (95% CI) were then pooled using a random effects model.

Results

Nine randomized controlled trials including 461 patients were identified in the overall analysis. CAP significantly decreased total cholesterol (TC) (WMD = −0.48, 95% CI: −0.63 to −0.34, I2= 0.00%) and low-density lipoprotein cholesterol (LDL-C) (WMD = −0.23, 95% CI: −0.45 to −0.02, I2 = 68.27%) among patients with MetS. No significant effects of CAP were found on triglycerides (TG) or high-density lipoprotein cholesterol (HDL-C) (WMD = −0.40, 95% CI: −1.50 to 0.71, I2 = 98.32%; WMD = −0.08, 95% CI: −0.21 to 0.04, I2 = 86.06%). Subgroup analyses indicated that sex and intervention period were sources of heterogeneity. The results revealed that CAP decreased TG levels in women (WMD = −0.59, 95% CI: −1.07 to −0.10) and intervention period <12 weeks (WMD = −0.65; 95% CI: −1.10 to −0.20). And there was no potential publication bias according to funnel plot, Begg' test and Egger regression test.

Conclusions

CAP supplementation is a promising approach to decreasing TC and LCL-C levels in patients with MetS. However, short-term (<12 weeks) use of CAP in women may also reduce TG levels.

Systematic Review Registration

Identifier: CRD42021228032.