Metabolic & Cardiometabolic
inositol decreases insulin resistance
📅 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
Inositol (myo-inositol / D-chiro-inositol) improves insulin resistance / metabolic measures in PCOS.
The evidence (7)
| Source | Grade | Stance | Quality | Finding |
|---|---|---|---|---|
| Mashhadi F et al 2026 · study_type: RCT | RCT | tested-null | low | n=196 infertile PCOS, 4-arm 12wk (metformin/MI 2000mg/Ziziphus/placebo): significant FBG/lipid/TyG gains reported for Ziziphus arm; myo-inositol arm's own metabolic advantage over placebo not distinctly reported |
| Bahadur A, et al. 2021 · Cureus | RCT | tested-null | moderate | Metformin+MI/DCI vs metformin: NO significant difference in fasting insulin or HOMA-IR (NS testosterone/glucose). |
| Duan M et al 2026 · study_type: meta-analysis | meta-analysis | supports | moderate | Umbrella review, 13 MAs/85 GRADE items (0% high, 41% very-low): HOMA-IR MD -1.14 (95%CI -1.35,-0.94, p<0.00001); fasting insulin MD -23.40 pmol/L (95%CI -32.80,-14.01, p<0.00001) vs placebo/FA |
| Fitz V, et al. 2024 · J Clin Endocrinol Metab | meta-analysis | mixed | moderate | 30 trials (n=2230): myo-inositol/DCI may improve SOME metabolic measures, DCI maybe ovulation, but no effect on other outcomes; low GRADE certainty. Authors' explicit verdict: limited and inconclusive. |
| Tienforti D et al 2026 · Clin Endocrinol (Oxf) | meta-analysis | mixed | moderate | OFF-SCOPE for this claim: the meta-analysis pools no insulin-resistance outcome. 'Primary outcomes were serum total testosterone (TT), calculated free testosterone (cFT), free androgen index (FAI), and sex hormone-binding globulin (SHBG). Prespecified subgroup analyses explored differences according to body mass index (BMI) and insulin resistance (HOMA-IR).' HOMA-IR is a stratifier, not an outcome. What the paper found, on androgens, across 9 RCTs and 440 women with PCOS: 'Inositol supplementation was associated with significant reductions in TT (SMD -1.30; 95% CI -2.17 to -0.42), cFT, and FAI, together with an increase in SHBG', with 'Substantial heterogeneity ... observed for several outcomes'. CORRECTION to the previous extract, which read 'NO sig HOMA-IR improvement in women with IR analyzed independent of BMI': the paper reports no pooled HOMA-IR result. The sentence that was paraphrased -- 'No significant improvements were detected in overweight or obese women, nor in women with insulin resistance when considered independently of BMI' -- sits in the RESULTS paragraph about total testosterone and refers to ANDROGEN improvements within an insulin-resistant subgroup. Outcome and moderator were transposed. Abstract-grade read; Europe PMC full text for PMC13326987 returned empty. |
| Delavar MA et al 2025 · study_type: meta-analysis | meta-analysis | supports | moderate | 18-RCT cardiometabolic MA (NOT PCOS-restricted): significant HOMA-IR/glucose/insulin reductions but I2=85-91% (very high heterogeneity), moderate GRADE. Off-scope population + heterogeneity -> low weight. |
| Gul M et al] # corrected 2026-08-17 from PubMed; was [et al. 2025 · Naunyn Schmiedebergs Arch Pharmacol | RCT | supports | moderate | MI+DCI 40:1 improved HOMA-IR (p<0.001), SHBG (p=0.021), ovarian volume, menses — but metformin slightly superior. |
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