Effects of Chromium Supplementation on Lipid Profile: an Umbrella of Systematic Review and Meta-analysis

Dyslipidemia is one of the most well-established modifiable risk factors for cardiovascular disease (CVD) development. Several meta-analyses have revealed the improving effects of chromium on dyslipidemia, while some studies have reported controversial results. This study aimed to summarize meta-analyses of randomized controlled trials (RCTs) that examined the effects of chromium supplementation on lipid profiles in adults. The literature search was conducted using Embase, Scopus, Web of Science, Cochrane Central Library, and PubMed databases with appropriate keywords from the beginning to May 2022. Based on the pooled analysis results, a random-effects model was used to determine the effects of chromium on blood lipid levels. Heterogeneity, publication bias, and sensitivity analysis were also evaluated using standard methods. A total of eight meta-analyses were included in this study. The pooled analysis of eight meta-analyses did not find any significant effect of chromium supplementation on triglycerides (TG) (ES = - 0.20 mg/dl; 95% CI: - 0.50, 0.10, p = 0.185), total cholesterol (TC) (ES = - 0.14 mg/dl, 95% CI: - 0.43, 0.16; p = 0.369), low-density lipoprotein cholesterol (LDL-c) (ES = - 0.08 mg/dl; 95% CI: - 0.19, 0.03; p = 0.142), and high-density lipoprotein cholesterol (HDL-C) levels (ES: 0.05 mg/dl, 95% CI: - 0.05, 0.14, p = 0.312). However, subgroup analysis by the intervention dose suggested that chromium supplementation in doses higher than 500 mu g/day could significantly decrease TG. The available evidence proposes no beneficial effects of chromium intervention on blood lipids. As a result, it cannot be used as a single therapy to treat adults with lipid abnormalities.