From the Research
Diindolylmethane (DIM) can increase Sex Hormone Binding Globulin (SHBG) levels in the body by modulating estrogen metabolism, which indirectly affects SHBG production, as suggested by the most recent and highest quality study available 1.
Mechanism of Action
DIM, a compound found in cruciferous vegetables like broccoli and cabbage, works primarily by promoting the metabolism of estrogen into beneficial 2-hydroxy estrogens rather than potentially harmful 16-hydroxy estrogens. This shift in estrogen metabolism signals the liver to produce more SHBG.
Effects on SHBG Levels
Higher SHBG levels help regulate the amount of free testosterone and estrogen in the bloodstream by binding to these hormones, making them less bioavailable.
Clinical Implications
This effect can be particularly beneficial for conditions associated with hormone imbalances such as PCOS, certain hormone-sensitive cancers, and estrogen dominance.
Important Considerations
The increase in SHBG from DIM supplementation typically occurs gradually over several weeks of consistent use. People taking hormone medications or those with hormone-sensitive conditions should consult with a healthcare provider before starting DIM, as the resulting changes in hormone binding could affect their treatment efficacy, as noted in various studies including 2, 3, 4, and 5.
Key Points to Consider
- DIM modulates estrogen metabolism to increase SHBG production
- Increased SHBG levels regulate free testosterone and estrogen in the bloodstream
- Beneficial effects for conditions like PCOS, hormone-sensitive cancers, and estrogen dominance
- Gradual increase in SHBG levels over several weeks of consistent DIM use
- Consult a healthcare provider before starting DIM, especially for those on hormone medications or with hormone-sensitive conditions