Exercise-induced modulation of gut microbiota in individuals with obesity and type 2 diabetes: a systematic review and meta-analysis.
Level 1 - systematic review of randomized trials
Systematic review and meta-analysis of intervention studies
PubMed 41070132 · doi:10.3389/fmicb.2025.1671975
What was done
A systematic review and meta-analysis of 19 studies encompassing 1,062 participants examined the effects of exercise interventions on gut microbiota in individuals with obesity and type 2 diabetes (T2D). The analysis evaluated alpha-diversity indices (Shannon, Simpson, Chao1, observed OTUs) and taxonomic composition, with subgroup analyses by exercise type and age.
What was found
Exercise significantly increased the Shannon index in both obesity (SMD = 0.40, 95% CI [0.15, 0.65], P = 0.002) and T2D (SMD = 0.48, 95% CI [0.08, 0.88], P = 0.02). Chao1 index improved significantly in obesity (SMD = 0.45, 95% CI [0.06, 0.85], P = 0.03), while Simpson index and observed OTUs showed no significant change. Combined exercise yielded larger effects than aerobic exercise alone in both obesity (SMD = 0.42, P = 0.02) and T2D (SMD = 0.69, P = 0.04). Individuals under 50 years demonstrated greater responsiveness (obesity: SMD = 0.32, P = 0.027; T2D: SMD = 0.86, P = 0.003). Qualitative analysis showed consistent enrichment of butyrate producers (*Roseburia*, *Faecalibacterium prausnitzii*) and *Akkermansia muciniphila*, whereas the Firmicutes/Bacteroidetes ratio and genera such as *Prevotella* and *Bacteroides* varied across studies.
Why it matters
This review provides quantitative evidence that structured exercise, particularly combined aerobic and resistance training, can improve gut microbial diversity and enrich beneficial taxa in metabolic disease.
Limits
The abstract does not specify whether all included studies were randomized controlled trials. Average sample size per study was modest (~56 participants), and key taxonomic markers (e.g., Firmicutes/Bacteroidetes ratio, genus-level abundances) showed heterogeneous, inconsistent responses across the included literature without reported adjustment for dietary intake.
Cited by
- supports Exercise has been shown to increase butyrate-producing bacteria in the gut microbiome.