40:1 myo-inositol d-chiro-inositol ratio
40:1 myo-inositol d-chiro-inositol ratio
Myo-inositol and D-chiro-inositol are two of nine inositol stereoisomers that work together as insulin messengers but play distinct roles: myo-inositol supports glucose transporter activation and FSH signaling in the ovaries, while D-chiro-inositol drives glycogen synthesis and storage in insulin-sensitive tissues. The body normally maintains roughly a 40:1 myo-to-D-chiro ratio in plasma, and research consistently shows this is the most effective ratio for PCOS, because excess D-chiro-inositol can impair egg quality and raise androgens. This guide compares the two forms across mechanism, PCOS and fertility outcomes, dosing, and safety, so you can decide whether myo-inositol alone or a 40:1 combination suits your goals.