Effect of Sucralose Consumption on Gut Microbiota: A Systematic Review and Meta-Analysis of Randomized Controlled...

Sucralose is a widely consumed non-nutritive sweetener, with approximately 85% reaching the colon unmetabolized and directly interacting with the gut microbiota. Despite regulatory approval, its impact on microbial ecology and metabolic outcomes remains inconclusive. Previous meta-analyses included only two human studies and did not integrate microbiota, short-chain fatty acids, and metabolic parameters. This systematic review and meta-analysis evaluated the effects of sucralose on gut microbiota composition, alpha diversity, short-chain fatty acid production, and metabolic parameters in healthy adults based on randomized controlled trial evidence. A systematic search of PubMed, Scopus, and Google Scholar was conducted in May 2026 following PRISMA guidelines. Risk of bias was assessed using Cochrane RoB 2.0, and meta-analysis employed a REML random-effects model. Ten randomized controlled trials involving 8-61 participants per study (total across intervention and control groups) met the inclusion criteria; seven provided data for meta-analysis. Sucralose did not significantly alter alpha diversity (Shannon index: SMD = -0.00; 95% CI -1.16 to 1.15; p = 0.99; I² = 25.67%), fasting blood glucose (SMD = -0.04; 95% CI = -0.63 to 0.56; p = 0.88; I² = 69.61%), and HOMA-IR (SMD = -0.13; 95% CI = -0.36 to 0.10; p = 0.212; I² = 0.00%). Butyrate showed a numerical decrease, although the pooled effect was not statistically significant and substantial heterogeneity was observed. Overall, the available evidence from short-term randomized controlled trials did not demonstrate statistically significant effects of sucralose consumption on the evaluated microbiota and metabolic outcomes. Standardized, longer-duration randomized controlled trials with inert comparators are needed.