What is Diindolylmethane
What it is:
- A compound formed when the body breaks down indole-3-carbinol (from cruciferous veggies like broccoli, kale, Brussels sprouts).
- Studied for its effects on estrogen metabolism, hormone balance, and cancer prevention.
1. Estrogen Metabolism & Hormone Balance
- DIM promotes the conversion of estrogen into “good estrogens” (2-hydroxyestrone) rather than “bad estrogens” (16α-hydroxyestrone), which are linked to cancer risk.
- Zeligs et al. (1998, J Nutr Biochem): Showed DIM alters estrogen metabolism toward protective pathways.
- Widely studied in context of PMS, menopause, PCOS, and estrogen dominance.
2. Breast & Prostate Cancer
- Breast cancer:
- Dalessandri et al. (2004, Cancer Epidemiol Biomarkers Prev): In women at risk for breast cancer, indole-3-carbinol/DIM supplementation shifted estrogen metabolism toward protective metabolites.
- DIM may also enhance the effect of tamoxifen in hormone-sensitive breast cancer (preclinical studies).
- Prostate cancer:
- Le et al. (2003, Biochem Pharmacol): DIM inhibited androgen receptor signaling in prostate cancer cells.
- Some pilot human trials suggest DIM supplementation slows PSA progression in men with prostate issues.
3. Anti-Inflammatory & Immune Effects
- Preclinical data: DIM shows anti-inflammatory, antioxidant, and immunomodulatory effects.
- May enhance natural detox pathways (phase I & II liver enzymes).
4. Weight & Metabolism
- Early studies suggest DIM may improve fat metabolism and reduce inflammation in obesity-related conditions, but human evidence is limited.
💊 Dosing in Studies
- Typical research dose: 100–300 mg/day.
- Supplements often sold in the 100–200 mg range.
⚠️ Safety
- Generally safe at standard doses.
- Mild side effects: GI upset, dark urine, headache.
- High doses may interfere with hormone therapies—caution for those on estrogen blockers or hormone replacement.



