The association of dietary polyphenols with obesity: a systematic review and meta-analysis.

BACKGROUND AND AIM: Accumulating evidence has proposed that dietary polyphenols may be linked to lower odds of obesity; nevertheless, the results are inconclusive. This meta-analysis was performed to examine the relationship between dietary intake of polyphenols and the odds of obesity.

METHODS

A systematic literature search in PubMed, Web of Science, and Scopus was conducted up to April 2025 to obtain all eligible studies. Odds ratios (OR) and 95% confidence intervals (95%CI) were pooled using the random effects model to test the odds of obesity (assessed by body mass index) for the highest versus the lowest intakes of total, subclasses and individual polyphenols.

RESULTS

A total of 3,113 studies were retrieved, of which 3,103 unrelated studies were excluded. Finally, 10 studies with 106,302 participants were included in the meta-analysis. When different polyphenolic compounds were pooled, they were linked to lower odds of obesity (OR: 0.91; 95%CI: 0.85–0.97), with significant evidence of heterogeneity (I2 = 84.0%, P < 0.001). The association was not modified by the age of participants. Higher intakes of total flavonoids (OR: 0.77; 95%CI: 0.64–0.92) and isoflavones (OR: 0.93; 95%CI: 0.88–0.98) were also significantly linked to the reduced odds of obesity. Moreover, a higher intake of flavonols was protective against obesity in some subgroups. No significant association was found for flavones, flavanones, flavanols, and anthocyanins. In the dose-response meta-analysis, the association of total flavonoids with obesity did not follow a linear (P = 0.18) or non-linear (P nonlinearity = 0.18) pattern.

CONCLUSION

The findings of this meta-analysis revealed that higher polyphenol intake is associated with decreased odds of obesity. CLINICAL TRIAL REGISTRATION: Not applicable.