Indole-3-Carbinol (I3C)

Tier 2 — promising · Estrogen metabolism · Cancer prevention

Found in cruciferous vegetables, I3C shifts estrogen metabolism toward less potent forms. Some observational and early clinical studies suggest benefit in estrogen-sensitive conditions. I3C converts to DIM and other compounds in the stomach, making effects unpredictable. DIM supplements provide more consistent results. Interacts with CYP-metabolised medications.

Dose: 200–400 mg/day I3C; converts to DIM in the stomach; DIM may be more reliable