In plain terms: Inositol (Myo-inositol) has some human trial evidence supporting it, but the evidence is not yet strong enough for EBL to call it established. It is worth knowing about and worth discussing with your clinician.
Inositol (Myo-inositol)
The evidence as the record states it
Greff et al. (Reproductive Biology and Endocrinology, 2023; PMID 36703143): meta-analysis of 26 randomized trials, 1,691 women with PCOS, any inositol against placebo or metformin; against placebo, inositol raised the chance of a regular menstrual cycle (1.79 times) and lowered glucose, insulin area under the curve, BMI and androgens, and it was non-inferior to metformin on most outcomes. Jethaliya et al. (Reprod Sci, 2022; PMID 35477841): meta-analysis of 17 randomized trials, 1,083 women with PCOS, myo-inositol compared with folic acid, metformin or oral contraceptives; no significant difference in fasting insulin, fasting glucose or HOMA against those comparators, which is a comparison with active treatment, not with placebo. Grade B: placebo-controlled pooled evidence on metabolic and reproductive surrogates, specific to PCOS.
Why Grade B and not Grade A
Grade B reflects moderate human evidence -- typically a single strong trial, multiple smaller trials, or surrogate endpoint data without hard clinical outcome replication. To reach Grade A, Inositol (Myo-inositol) would require at least one additional independent randomized trial demonstrating a hard clinical endpoint or objectively measured functional outcome in a comparable population.
What would move this grade
An independent randomized trial demonstrating a hard clinical endpoint -- mortality, major adverse event, or objectively confirmed functional improvement -- in an adequately powered sample, with results independently replicated, would support Grade A.
How this was studied
Form: Myo-inositol (Jethaliya 2022 meta-analysis, PMID 35477841); "any inositols" compared with metformin or placebo (Greff 2023 meta-analysis, PMID 36703143). · Dose: not stated in the cited abstracts · Population: Women with polycystic ovary syndrome: 26 randomized trials, 1,691 patients (Greff 2023 meta-analysis, PMID 36703143); 17 randomized trials, 1,083 patients, with comparators of folic acid (7 trials), metformin (8) and oral contraceptives (2) (Jethaliya 2022 meta-analysis, PMID 35477841). · Duration: not stated in the cited abstracts