Diindolylmethane, or DIM, forms when the body breaks down cruciferous vegetables like broccoli, cabbage, and kale. It shifts estrogen breakdown toward the 2-hydroxy pathway and away from other routes that produce stronger estrogen metabolites.
People use DIM to promote healthier estrogen balance, often when they feel their estrogen levels are too high relative to progesterone. Men sometimes take it to support normal prostate cell function.
Take DIM with a meal that contains fat so the body absorbs it properly. Capsules and softgels are typical, and most products use a standardized extract. Daily, consistent intake works best.
Side effects can include stomach upset or darker urine. DIM may interact with prescription hormones like birth control pills or hormone replacement therapy, and its safety during pregnancy and breastfeeding is unknown. Caution is advised if you take blood thinners or thyroid medication.