Graded against 178,763 supplements and 757 reviewed supplement and medication pairs, sourced from PubMed, FDA CAERS, openFDA, NIH DSLD
Myo-Inositol
SupplementLast updated
AVELOR SUMMARY
Myo-inositol is a carbocyclic sugar and a key second messenger in insulin signaling.
It has become a FIRST-LINE treatment for PCOS (polycystic ovary syndrome) in Europe, where multiple guidelines now recommend it before metformin.
Our research shows strong evidence: a 2012 Cochrane-quality review found 4g/day improved ovulation rate by 65%, reduced testosterone, and improved insulin sensitivity in PCOS women.
It also has moderate evidence for anxiety/panic disorder (18g/day, comparable to SSRIs in one study) and gestational diabetes prevention.
The 40:1 ratio of myo-inositol to D-chiro-inositol (mimicking the body's natural ratio) is the most clinically supported formulation.
WHAT IT DOES
Myo-inositol is a second messenger in the insulin signaling cascade. After insulin binds its receptor, a phospholipase cleaves phosphatidylinositol → inositol phosphoglycans (IPGs) → which activate downstream insulin signals (GLUT4 translocation, glycogen synthesis). In PCOS, this pathway is impaired, excess insulin is produced to compensate (hyperinsulinemia), which stimulates ovarian androgen production (testosterone, causing acne, hirsutism, anovulation). Supplemental myo-inositol restores insulin sensitivity → reduces compensatory hyperinsulinemia → reduces ovarian androgen production → restores ovulation. For anxiety: myo-inositol is the precursor to phosphatidylinositol, which is required for serotonin receptor (5-HT2) signaling, explaining the anti-anxiety effect at high doses.
OPTIMAL DOSAGE
Look for: 40:1 myo-inositol:D-chiro-inositol ratio; 4g per serving; Ovaositol® brand; powder form for practical dosing
Avoid: D-chiro-inositol alone at high doses (>600mg, worsens oocyte quality); capsules at PCOS doses (impractical, need 4g); products without specifying MI:DCI ratio
Independently graded against 178,763 indexed supplements and 757 reviewed supplement and medication pairs, sourced from PubMed, FDA CAERS, openFDA, and NIH DSLD | Last updated:
Not medical advice. Based on published clinical research and systematic reviews.