Myo-inositol

Tier 2 — promising · PCOS · Metabolic · Mental health

Myo-inositol is the most abundant naturally occurring isomer of inositol, functioning as a precursor to phosphoinositide second messengers in insulin and serotonin signaling. Clinical trials consistently show improvements in insulin sensitivity, menstrual cycle regularity, and androgen levels in women with PCOS at 2–4 g/day. A 2024 systematic review informing international PCOS guidelines (Fitz, PMID 38163998, 30 trials, n=2,230) found evidence of benefit for metabolic outcomes though acknowledged overall evidence as limited. At higher doses (12–18 g/day), it also shows psychiatric effects…

Dose: 2,000–4,000 mg/day for PCOS/metabolic; 40:1 myo:D-chiro-inositol combination preferred; 12–18 g/day for psychiatric applications.