Curcumin supplementation contributes to relieving anthropometric and glycemic indices, as an adjunct therapy: A meta-research review of meta-analyses

Background: Curcumin, a natural polyphenolic compound, can affect anthropometric and glycemic indices; however, the findings of existing meta-analyses are controversial. Study design: The current umbrella meta-analysis was performed among present systematic reviews and meta-analyses to investigate the effect of curcumin supplementation on anthropometric and glycemic indices. Methods: A comprehensive systematic search was performed on Embase, PubMed, WOS, Scopus, and Cochrane Library to obtain peer-reviewed papers published before 30/November/2021. meta-analysis was conducted using the random-effects model. Results: 12 meta-analyses were included in the current study. Our results have revealed that the curcumin supplementation can significantly decrease body mass index (BMI) (ES: −0.26; 95 % CI: −0.38, −0.14, p < 0.001; I2 = 0.0 %, P = 0.842), body weight (BW) (ES: −0.55; 95 % CI: −0.99, −0.12, p = 0.013; I2 = 81.1 %, p < 0.001), waist circumference (WC) (ES: −0.66; 95 % CI: −1.23, −0.09, p = 0.023; I2 = 72.4 %, p = 0.003), fasting blood sugar (FBS) (ES: −1.63; 95 % CI: −2.36, −0.89, p < 0.001; I2 = 88.4 %, p < 0.001), homeostasis model assessment-estimated insulin resistance (HOMA-IR) (ES: −0.38; 95 % CI: −0.48, −0.28, p < 0.001;I2 = 35.9 %, p = 0.142), hemoglobin A1c (HbA1c) (ES: −0.44; 95 % CI: −0.67, −0.21, p < 0.001;I2 = 65.0 %, p = 0.014), and insulin (ES: −0.86; 95 % CI: −1.52, −0.21, p = 0.010; I2 = 92.5 %, p < 0.001). Conclusion: These findings recommend curcumin supplementation as a favorable intervention to improve anthropometric and glycemic indices

Can resveratrol supplementation affect biomarkers of inflammation and oxidative stress? An umbrella meta-analysis

Several meta-analyses exist in supporting the positive effects of resveratrol on inflammatory and oxidative stress biomarkers; however, the finding of some studies is inconsistent. Therefore, the objective of the current study was to investigate the effects of resveratrol on inflammatory and oxidative stress biomarkers in adults. Up until April 2022, we conducted a thorough and systematic search in PubMed, Scopus, Web of Science, Embase, and Google Scholar. Our results from 15 meta-analyses indicated that the resveratrol supplementation meaningfully decrease serum CRP (ES = −0.38, 95 % CI: −0.47, −0.30; p < 0.001) and TNF-α (ES = −0.32; 95 % CI: −0.54, −0.11; p = 0.004). However, the effect of resveratrol on IL-6, TAC, GPx, and SOD activity was not significant. The current umbrella meta-analysis supports the alleviating effects of resveratrol on inflammatory markers but does not suggest any beneficial effect on oxidative stress biomarkers. Therefore, to support this evidence, larger and well-designed trials are required