Supplement
DIM (diindolylmethane) forms when the body digests broccoli-family vegetables, and it influences how estrogen is processed. People look at it for HPV support and hormone balance, and the evidence is limited: studies found it raised a urinary estrogen ratio in a favorable direction and changed several estrogen metabolites. Those are hormone markers, not clinical outcomes, and in breast cancer patients, very limited research found lower tamoxifen metabolites, which may reduce its effectiveness.
- Updated
- How we grade
- 5 studies cited
- Best evidence
- Grade B
- Conditions studied
- 4
- Outcomes
- 5
- Graded outcomes
- 0131
Evidence by condition
- Strong
- Moderate
- Limited
- Very limited
Estrogen Metabolism
| Grade | Outcome | Effect | Size | Studies | People | Studies list |
|---|---|---|---|---|---|---|
| 2/16α-OHE1 Ratio Favorable increase in urinary 2/16α-OHE1 ratio (breast cancer biomarker) | Improves (the measure goes up) | Moderate effect | 200 people |
| Grade | Outcome | Effect | Size | Studies | People | Studies list |
|---|---|---|---|---|---|---|
| SHBG Levels Increased SHBG suggesting favorable hormone environment | Improves (the measure goes up) | Moderate effect | 130 people | |||
| Tamoxifen Metabolism CONCERNING: Reduced endoxifen and tamoxifen metabolites - may reduce efficacy | Improves (the measure goes down) | Moderate effect | 130 people |
Thyroid Disease
- Thyroid Tissue Uptake: improves
| Grade | Outcome | Effect | Size | Studies | People | Studies list |
|---|---|---|---|---|---|---|
| Thyroid Tissue Uptake DIM detectable in thyroid tissue after 14-day supplementation | Improves (the measure goes up) | Moderate effect | 20 people |
Hormone Balance
- Estrogen Metabolites: improves
| Grade | Outcome | Effect | Size | Studies | People | Studies list |
|---|---|---|---|---|---|---|
| Estrogen Metabolites Alters 6 of 10 estrogen metabolites measured | Improves (the measure goes up) | Moderate effect | 150 people |
Key findings
- 2/16α-OHE1 RatioImproves (the measure goes up)
- SHBG LevelsImproves (the measure goes up)
- Thyroid Tissue UptakeImproves (the measure goes up)
Shop the evidence-backed picks
Third-party tested DIM products, in the forms the graded studies used where we can match them.
- Grade B
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Studies cited
5 studies from PubMed
- Diindolylmethane reduces endoxifen formation in breast cancer survivors on tamoxifen
- Phase I clinical trial of diindolylmethane in breast cancer survivors
- 3,3'-Diindolylmethane: safety and pharmacokinetics in healthy men
- Diindolylmethane modulates estrogen metabolism in patients with thyroid proliferative disease
- Effects of diindolylmethane on estrogen metabolism in healthy postmenopausal women