Supplements · Metabolic & Cardiometabolic
probiotics decreases insulin resistance
Part of: 🧪 Probiotics
📅 Last reviewed: 2026-07-15 ⓘ
Evidence ladder
How far up the ladder this claim has climbed. A high consensus on a low rung means "consistent so far," not "proven in people."
Top evidence so far: All trials, pooled (Meta-analysis)
How the studies fall
What the evidence shows
Probiotics/synbiotics improve insulin resistance in PCOS.
The evidence (7)
| Source | Grade | Stance | Quality | Finding |
|---|---|---|---|---|
| prob-2020 2020 · European journal of clinical nutrition | meta-analysis | supports | moderate | ↓HOMA-IR -0.69, ↓insulin, ↓CRP. |
| Bodake RD, Bidri SR, Chhabra E, Amreen SA 2026 · Annals of African medicine | observational | supports | low | Single-arm pre-post, n=90 PCOS women, multistrain probiotic 12wk. FBG, fasting insulin, HOMA-IR all improved P<0.001 vs baseline. No control/placebo arm; no CI or effect size given. |
| Hamsho M, Shkorfu W, Bensaoua M, Martins CEC, Hacıbayram H, Fadel A, Ranneh Y 2026 · Frontiers in endocrinology | meta-analysis | supports | moderate | MA of 6 RCTs, probiotic+metformin vs metformin alone in PCOS. HOMA-IR: MD -0.50, 95% CI -0.73 to -0.26, low-to-moderate heterogeneity. |
| prob-negligible-2019 2019 · Probiotics and antimicrobial proteins | meta-analysis | contradicts | moderate | No effect on HOMA-IR/FPG; 'negligible.' |
| umbrella-prebio-2023 2023 · Front Nutr | meta-analysis | supports | moderate | Umbrella review that re-pools primary RCTs itself (largest MA per outcome plus missed trials; random effects) — meta-analysis, not a copying overview. PCOS: 'probiotic supplementation significantly reduced HOMA-IR compared to the control group (WMD: −0.29, 95% CI: −0.57 to −0.02, p = 0.03)', I2 33.8%, 4 RCTs, moderate GRADE certainty. Synbiotics HOMA-IR WMD −0.82 (−1.09 to −0.56), low certainty. 7 of 9 included MAs rated low/critically-low AMSTAR-2. |
| synbiotic-pcos-2023 2023 · Critical reviews in food science and nutrition | meta-analysis | supports | moderate | Pro/pre/synbiotics improved IR/lipids/CRP in PCOS. |
| Sun Z, Zhang R, Tian X, Li T, Liu Z 2026 · BMC Endocr Disord | meta-analysis | mixed | moderate | MA of 11 RCTs, n=780, PCOS. Fasting insulin reduced (MD -1.41, 95% CI -2.76 to -0.05) but HOMA-IR NOT significant. Testosterone, TG, LDL, BMI significantly improved (GRADE high); fasting insulin GRADE moderate. |
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Educational only, not medical advice. Grades and scores reflect published evidence weighted by study design and quality; see the methodology.