Resveratrol supplements confer minimal benefits in T2D, MetS, NAFLD

Supplementation with resveratrol does not appear to provide much benefit in the management of cardiometabolic risk factors in patients with type 2 diabetes (T2D), metabolic syndrome (MetS), and nonalcoholic fatty liver disease (NAFLD), suggests a study.

However, a clinically important effect has been noted in the case of glycated haemoglobin (HbA1c), subject to some limitations such as short-term follow-up and small sample size.

A team of investigators searched the databases of PubMed, Scopus, and ISI Web of Science from inception to May 2021. They recalculated the mean difference and its 95 percent confidence interval (CI) for each meta-analysis using a random-effects model. The certainty of evidence was rated using the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) approach.

Overall, 11 meta-analyses corresponding to 29 outcomes in 1,476 individuals with T2D, 17 meta-analyses reporting 26 outcomes in 727 participants with MetS, and 10 meta-analyses with 24 outcomes reported in 271 patients with NAFLD were identified.

Resveratrol supplementation showed beneficial effects on outcomes such as blood pressure, lipid profile, glycaemic control, and insulin resistance in T2D, waist circumference in MetS, and body weight and inflammation markers in NAFLD. However, the magnitude of the effect was inconsequential, the certainty of evidence was very low to low, and the number of trials was few for almost all outcomes.

For HbA1c, evidence showed that resveratrol could deliver positive and clinically significant effects in the short term (<12 weeks; mean difference, –1.05 percent, 95 percent CI, –2.09 to –0.02; n=6; GRADE: moderate).

“Uncertainty remains about the estimates of the effects for resveratrol supplementation, including the certainty of the evidence for each estimate and the magnitude of the observed impact based on the minimal important difference,” the investigators said.