DIM (diindolylmethane)
C17H14N2
Two indole rings joined by a single carbon bridge. Your body makes it from a compound in broccoli, cabbage, and kale.
Evidence current to September 2026
What it's pushed for
What the research shows
In human studies, DIM measurably changes how the body breaks down estrogen. A 2020 systematic review of 22 human trials found shifts in estrogen metabolism and in a hormone-binding protein.
Changing a lab marker isn't the same as improving symptoms or treating disease. The same review noted there's no clinical evidence that DIM treats the cancers it's often marketed for.
For endometriosis, the research so far is in animals and cells, not people.
Myth vs. fact
Myth"DIM detoxes estrogen."
FactIt shifts which estrogen byproducts your body makes. Whether that improves endometriosis symptoms hasn't been tested in human trials.
Who should check with a clinician first
Anyone on hormone therapy or hormone-sensitive treatment. In a randomized trial, DIM lowered levels of the breast cancer drug tamoxifen and its active forms. A 2025 study in women using estrogen patches suggested clinicians ask about DIM because it may affect hormone therapy.
What to look for on the label
Look for the DIM amount listed clearly, not hidden inside a "hormone balance" blend. Major trials used an absorption-enhanced form, so plain DIM powder may not match what was studied.
How to read any supplement labelSources
- Systematic review of human DIM trials (Nutrition and Dietary Supplements) (2020)
- Randomized trial of DIM in women taking tamoxifen (Cancer Epidemiology, Biomarkers & Prevention) (2017)
- DIM and transdermal estradiol in postmenopausal women (PubMed) (2025)
- Indole-3-carbinol in a mouse model of endometriosis (PubMed) (2022)
This guide is for education, not medical advice. Supplements can interact with medications and health conditions. Talk with your clinician or pharmacist before starting, stopping, or changing anything. The Lily Perspective earns no income from any supplement brand or retailer.