Nutr J. 2026 Jul 13. doi: 10.1186/s12937-026-01364-0. Online ahead of print.
ABSTRACT
BACKGROUND: Short-chain fatty acids produced by microorganisms living in the gastrointestinal tract are known to have numerous beneficial effects. Because certain probiotic strains may influence short-chain fatty acid production, probiotic supplementation has been proposed as a potential strategy to modify faecal short-chain fatty acid concentrations. Our aim was to investigate whether probiotics modify faecal short-chain fatty acid levels in healthy populations via systematic review and meta-analysis.
METHODS: We performed a systematic search of the MEDLINE, Embase, and Cochrane databases on 12/04/2024. We analysed exclusively randomized controlled trials meeting all the following criteria: population: healthy people; intervention: probiotic supplementation; control: no probiotic supplementation; outcome: faecal short-chain fatty acid concentrations. A total of 9217 articles were reviewed, 21 of which met the preset inclusion criteria. Twelve articles, including 541 subjects, were eligible for meta-analysis of changes in faecal short-chain fatty acid concentrations. The standardized mean difference (SMD, Hedges’ g) was chosen as the effect indicator due to the different measurement techniques used. A random-effects model was used to estimate SMD with 95% confidence interval (CI) due to the expected heterogeneity.
RESULTS: No statistically significant differences were detected in the faecal butyrate (SMD = 0.07, 95%CI:[(-)0.16 – 0.30]), acetate (SMD = 0.06, 95%CI:[(-)0.14 – 0.27]), and propionate (SMD = 0.09, 95%CI:[(-)0.07 – 0.25]) levels between individuals taking and not taking probiotics.
CONCLUSIONS: Our results suggest that probiotic intake has a minor effect on faecal short-chain fatty acid concentrations, but this effect is not statistically detectable in healthy individuals. Thus, there is insufficient evidence of statistically significant effect of probiotic supplementation on stool short-chain fatty acid concentrations in healthy individuals.
TRIAL REGISTRATION: Research protocol was registered in PROSPERO (CRD42022286137).
PMID:42437924 | DOI:10.1186/s12937-026-01364-0
