Effects of Dietary Fruit and Vegetable Consumption on Prediabetes: A Systematic Review and Meta-Analysis

Background/Objectives: Previous studies have reported inconsistent findings regarding the association between fruit and vegetable consumption and prediabetes. Therefore, we aimed to investigate this association using a meta-analysis, following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Methods: Relevant studies were identified through systematic searches of PubMed, EMBASE, and the Cochrane Library through January 2026 using predefined keywords. Pooled odds ratios (ORs) with 95% confidence intervals (CIs) were estimated using a random-effects model. Results: A total of 20 observational studies were included, comprising 16 cross-sectional studies, one case-control study, and three cohort studies, with 24,660 cases of prediabetes among 182,387 participants. Higher fruit and vegetable consumption was significantly associated with a lower risk of prediabetes (OR, 0.82; 95% CI, 0.74-0.91; I² = 91.9%). Subgroup analysis by study design showed a significant association in cross-sectional studies (OR, 0.81; 95% CI, 0.70-0.94; I² = 91.6%; n = 16), whereas cohort studies showed no significant association (OR, 0.97; 95% CI, 0.92-1.02; I² = 15.1%; n = 3). Subgroup analyses by sex indicated a significant inverse association among male participants (OR, 0.77; 95% CI, 0.61-0.97; I² = 63.3%; n = 4), but not among female participants (OR, 0.97; 95% CI, 0.69-1.37; I² = 82.1%; n = 3). Conclusions: Overall, this meta-analysis indicates that greater fruit and vegetable consumption is associated with a reduced risk of prediabetes. However, additional prospective cohort studies are required to clarify potential confounding factors and confirm this association.