Whole grapes or grape products on body weight, anthropometrics, and adipokines: systematic review and meta-analysis of randomized controlled trials

This meta-analysis aims to compile all randomised controlled trials (RCTs) that examined the effects of grapes or grape products on adult anthropometric measures and serum adipokines. We searched PubMed, Scopus, Google scholar, Web of Science and CENTRAL databases published before January 2022. Random-effects model was used to combine mean differences between intervention and placebo groups. A minimal reduction was revealed for BMI following consumption of grapes/grape products [weighted mean difference (WMD): −0.14 kg]; however, no significant effects were observed on body weight, except for trials conducting in female (<i>n</i> = 3 studies; WMD: −0.68 kg), and those enrolled patients with metabolic syndrome (<i>n</i> = 3 studies; WMD: −0.62 kg). No significant effect was found for waist circumference, body fat, waist to hip ratio, serum level of leptin and adiponectin. Our findings showed that grapes or grape products have no significant anti-obesity effects on body weight, anthropometric measures, or adipokines. However, BMI showed a trivial decrease, which should not be considered given the low quality of the studies.