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    General Health IngredientsNatural

    Inositol (Myo-Inositol)

    Also known as: inositol, Myo-Inositol, Myo‑inositol, MI, D-chiro-inositol (related isomer)

    Systematic reviews and meta-analyses of randomized trials report that myo-inositol or related inositol isomers may improve some metabolic measures in women with PCOS and could have modest effects on ovulation; effects on other reproductive or anthropometric outcomes are uncertain. Compared with metformin, inositol probably causes fewer gastrointestinal adverse events, but overall evidence quality has been judged limited or low to very low.

    Last reviewed: 2026-10-14 · 3 indexed studies

    Evidence Score
    46/100
    Polycystic ovary syndrome (PCOS)Assisted reproduction / fertility supportMetabolic/hormonal support in women
    Data Completeness4/4 · 100%
    Evidence ScoreDosageSafetyLinked Studies

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    Overview

    Myo-inositol is a stereoisomer of inositol commonly used as an oral supplement, particularly in women with polycystic ovary syndrome (PCOS) or for fertility support. Clinical trials and meta-analyses have examined its effects on metabolic, reproductive and some hormonal outcomes, with mixed and limited certainty of evidence.

    Mechanism & Function

    Mechanism of Action

    Proposed insulin-sensitising action through inositol-containing signalling pathways relevant to insulin and gonadotropin signalling; mechanistic claims here are inferred by the reviews but not demonstrated directly in the provided clinical abstracts.

    Physiological Role

    Inositols are components of intracellular signalling molecules involved in insulin and hormonal pathways; myo-inositol is considered to influence metabolic and ovarian function through these pathways.

    Primary Pathways

    Insulin signallingOvarian/gonadotropin signallingCellular second messenger (phosphoinositide) pathways

    Performance / Health Relevance

    Not primarily an ergogenic or cognitive ingredient; clinical trials focus on reproductive and metabolic endpoints in women with PCOS or diminished ovarian reserve rather than on athletic performance.

    Evidence Review

    Overall46/100
    Human Clinical29/100
    Meta-Analysis50/100
    Mechanistic65/100
    Real-World26/100
    Safety80/100

    Practical Use & Dosage

    Minimum Effective Dose
    Not established from the provided abstracts
    Optimal Range
    Not established from the provided abstracts
    Upper / Caution Level
    Not established from the provided abstracts
    Timing
    Not established from the provided abstracts
    Best Format
    Oral (capsule/tablet/powder) as used in clinical trials referenced in reviews
    Bioavailability
    Not detailed in the provided abstracts
    Absorption Considerations
    Not detailed in the provided abstracts

    Safety & Interactions

    Side Effects

    • •Gastrointestinal symptoms (less frequent than with metformin according to meta-analysis)
    • •Generally reported as mild in trials cited

    Contraindications

    • Not established in the provided abstracts

    Drug Interactions

    • •Not established in the provided abstracts

    Who Should Avoid

    • •Not established in the provided abstracts; pregnant or breastfeeding women should consult a clinician — evidence in fertility contexts is limited and should be discussed with a clinician

    Monitoring

    Monitor clinical outcomes relevant to indication (e.g. ovulation, metabolic measures) and adverse effects; discuss use with treating clinician for reproductive care

    Frequently Asked Questions

    Auto-generated from indexed evidence — dosage, safety, interactions, and more.

    When is Inositol (Myo-Inositol) typically used or indicated?

    Inositol (Myo-Inositol) is most commonly used for: Polycystic ovary syndrome (PCOS), Assisted reproduction / fertility support, Metabolic/hormonal support in women. Inositols are components of intracellular signalling molecules involved in insulin and hormonal pathways; myo-inositol is considered to influence metabolic and ovarian function through these pathways.

    How does Inositol (Myo-Inositol) work?

    Proposed insulin-sensitising action through inositol-containing signalling pathways relevant to insulin and gonadotropin signalling; mechanistic claims here are inferred by the reviews but not demonstrated directly in the provided clinical abstracts.

    What is the recommended dose of Inositol (Myo-Inositol)?

    The optimal range is Not established from the provided abstracts. with a minimum effective dose of Not established from the provided abstracts. Best taken: Not established from the provided abstracts. Upper / caution level: Not established from the provided abstracts.

    What are the side effects of Inositol (Myo-Inositol)?

    Reported side effects include: Gastrointestinal symptoms (less frequent than with metformin according to meta-analysis); and Generally reported as mild in trials cited. Monitoring: Monitor clinical outcomes relevant to indication (e.g. ovulation, metabolic measures) and adverse effects; discuss use with treating clinician for reproductive care

    Does Inositol (Myo-Inositol) interact with medications?

    Known or theoretical interactions: Not established in the provided abstracts. Always check with a clinician before combining with prescription medication.

    Who should avoid Inositol (Myo-Inositol)?

    Inositol (Myo-Inositol) is generally not recommended for: Not established in the provided abstracts; pregnant or breastfeeding women should consult a clinician — evidence in fertility contexts is limited and should be discussed with a clinician; and Not established in the provided abstracts.

    How strong is the evidence for Inositol (Myo-Inositol)?

    Evidence level: Limited (overall score 46/100), based on 3 indexed studies on SuppIndex.

    Research & References (3)

    Inositol for Polycystic Ovary Syndrome: A Systematic Review and Meta-analysis to Inform the 2023 Update of the International Evidence-based PCOS Guidelines.

    Meta-Analysis2024
    PubMed

    Systematic review and meta-analysis of inositol (myo-inositol or D-chiro-inositol) in PCOS including 30 trials (n = 2230) with 19 pooled in meta-analyses; evaluated hormonal, metabolic, reproductive and adverse outcomes to inform PCOS guidelines.

    Antioxidants and Fertility in Women with Ovarian Aging: A Systematic Review and Meta-Analysis.

    Meta-Analysis2024
    PubMed

    Meta-analysis of antioxidants for fertility in women with ovarian aging including 20 RCTs (n = 2617); compared different antioxidants (CoQ10, melatonin, myo-inositol, vitamins) and dose effects.

    Inositol for subfertile women with polycystic ovary syndrome.

    Meta-Analysis2018
    PubMed

    Systematic review (to July 2018) of oral inositol supplementation in subfertile women with PCOS including 13 trials (n = 1472) comparing myo-inositol versus placebo, standard care or other agents.

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    Research Overview

    Limited Evidence
    3Total Studies
    0Human Trials
    3Meta-Analyses
    2024Latest Study
    0Animal / In Vitro
    0Athlete Studies
    Primary data sourceClinical Patients
    Pooled evidence (meta-analysis / systematic review)Yes

    Cite this ingredient

    One-click citation export in APA, MLA, Chicago, BibTeX, or HTML. The URL below is stable and safe to link.

    Stable URL

    https://thesuppindex.com/ingredients/myo-inositol

    SuppIndex. (2026). Inositol (Myo-Inositol): Evidence summary, dosage and clinical studies. Retrieved October 16, 2026, from https://thesuppindex.com/ingredients/myo-inositol

    Based on 3 indexed studies · Evidence level: Limited.

    Goal Ratings

    Hormonal Support
    General Health
    Metabolic Health

    Stack Compatibility

    Often studied versus or alongside other fertility agents (e.g. metformin) and antioxidants; evidence is inconclusive regarding superiority or additive benefit

    Metabolic/hormonal support regimens used in PCOS care (often studied against metformin)Antioxidant regimens used in fertility care (cohort/comparative studies)