Supplement

Inositol

Also known as Myo-inositol, D-Chiro-inositol

Sugar alcohol, not a true vitamin, involved in insulin signal transduction and cell membrane structure; myo-inositol is well studied for improving insulin sensitivity and ovulation in PCOS, and for reducing panic and anxiety symptoms.

2linked conditions

20linked studies

On this pageEvidence Availability Outcomes & conditions →

Evidence

What the research actually shows

We link to relevant studies and leave interpretation to you and your healthcare professional.

Evidence analytics

Where the evidence is concentrated

Number of audited published findings for Inositol by condition. Drill into a pair page for the full breakdown.

Putative uses

Where people report using it and what trials suggest

Strong evidencePCOS: ovulation & insulin sensitivity (2-4 g myo-inositol)
Moderate evidencePCOS metabolic markers
Moderate evidenceGestational diabetes prevention
Moderate evidencePanic disorder / OCD adjunct (high dose)

Where the evidence is negative

Common claims the trials do not support

Non-PCOS fertility benefits unproven.
Depression evidence weak outside small trials.
Dose matters: 12-18 g/day used in psychiatric trials vs ~2 g in retail products.

Myo-inositol has the strongest PCOS evidence of any supplement in this set — insulin sensitivity and ovulation restoration at proper doses.

Safety notes: Well tolerated; GI gas at high doses; uterine contractions reported — care in pregnancy beyond first trimester.

Evidence grades reflect study quality and consistency, not marketing claims.

20studies referenced

19journals

1996–2025publication range

01Transdiagnostic reduction in cortical choline-containing compounds in anxiety disorders: a (1)H-magnetic resonance spectroscopy meta-analysisMaddock RJ, et al. · Molecular psychiatry · 2025PMID 40913113 ↗02The impact of ingestion of Bifidobacterium longum NCC3001 on perinatal anxiety and depressive symptoms: a randomized controlled trialFries LR, et al. · Scientific reports · 2025PMID 40175540 ↗03Comparative efficacy of combined myo-inositol and D-chiro inositol versus metformin across PCOS Phenotypes: enhancing ovarian function, ovulation, and stress response in a prospective clinical trialGul M, et al. · Naunyn-Schmiedeberg's archives of pharmacology · 2025PMID 39847053 ↗04Comparison of metformin with inositol versus metformin alone in women with polycystic ovary syndrome: a systematic review and meta-analysis of randomized controlled trialsKelly FA, et al. · Endocrine · 2025PMID 39331347 ↗05Myo-inositol Supplementation to Prevent Pregnancy Complications in Polycystic Ovary Syndrome: A Randomized Clinical Trialvan der Wel AWT, et al. · JAMA · 2025PMID 40920401 ↗

Search PubMed ↗Find clinical trials ↗

What trials found, in numbers

Summaries of published trial results for this compound, grouped by condition. Numbers are reported exactly as the researchers published them — we never calculate or convert.

How to read this table

Benefit: What the trial saw happen: whether the measured outcome moved in the helpful direction in that one study (the tag on each row: “Benefit seen”, “No clear benefit” or “Unclear”). It is a study result — not advice, and not a promise it will work for you.
Evidence: How strong the research behind that result is. A meta-analysis pools many studies (strongest); a systematic review collates them; an RCT tests against a control (placebo); observational studies only watch — they can suggest, not prove.
Effect size: How large the measured change was, exactly as the researchers published it. “No number reported” means the abstract gave no effect size — we never invent one.

In short: benefit is what was observed; evidence is how much you should trust the observation. A “Benefit seen” tag on a weak study counts for far less than the same tag on a meta-analysis.

Anxiety (3 outcomes)

Outcome measured	What trials found	Effect size	People studied	Duration	Type of evidence	Study
Anxiety and obsessive-compulsive symptoms	Inositol did not significantly improve anxiety or obsessive-compulsive symptoms compared to placebo.No clear benefit	no number reported	—	—	Meta-analysis · 2014	PMID 24424706
Depressive symptoms	Inositol did not significantly improve depressive symptoms compared to placebo.No clear benefit	no number reported	—	—	Meta-analysis · 2014	PMID 24424706
Treatment discontinuation	Inositol did not significantly change discontinuation rates compared to placebo.

Outcomes & conditions

Why people look into Inositol — and what they report

Associated conditions and community-reported outcomes, wrapped together on one page. Aggregates appear only once enough reports arrive.

Outcomes & conditions →

Important: This page reflects observational, aggregate-only community reporting and independent published research. It is not medical advice, and it does not claim any compound treats, cures, or is effective for any condition. Always consult a qualified healthcare professional before starting, stopping, or changing any supplement or treatment.

Availability

Where to get Inositol (UK)

How this compound is sold in the UK, and where our readers typically find it.

Retailer search links — we may earn commission on purchases at no cost to you. Commission never affects our evidence ratings.

Search Inositol on Amazon UK →Search Inositol on Holland & Barrett →Search Inositol on iHerb →

Outcome measured	What trials found	Effect size	People studied	Duration	Type of evidence	Study
Acne score	Myo-inositol and D-chiro inositol significantly improved acne score compared with placebo over 6 months.Benefit seen	no number reported	137	6 months	RCT · 2015	PMID 25670222
Endocrine parameters	Myo-inositol and D-chiro inositol significantly improved endocrine parameters compared with placebo over 6 months.Benefit seen	no number reported	137	6 months	RCT · 2015	PMID 25670222
Insulin resistance	Myo-inositol and D-chiro inositol significantly improved insulin resistance compared with placebo over 6 months.Benefit seen	no number reported	137	6 months	RCT · 2015	PMID 25670222
Menstrual cycle regularity	Myo-inositol and D-chiro inositol significantly improved menstrual cycle regularity compared with placebo over 6 months.Benefit seen	no number reported	137	6 months	RCT · 2015	PMID 25670222
Metabolic parameters	Myo-inositol and D-chiro inositol significantly improved metabolic parameters compared with placebo over 6 months.Benefit seen	no number reported	137	6 months	RCT · 2015	PMID 25670222