What the evidence says. Graded mixed: DIM reliably nudges the 2/16-hydroxyestrone ratio, but trials testing whether that translates into clinical benefit are largely null — it did not change cervical cytology or HPV clearance, and the popular acne, weight and 'estrogen detox' claims have no controlled human evidence. (Mixed evidence: Conflicting results across studies; benefit uncertain.)
What is DIM (Diindolylmethane)?
DIM (Diindolylmethane) is a longevity supplement used for shift estrogen metabolite ratio. NutriDex grades the human evidence as Mixed. DIM is a compound your gut forms from indole-3-carbinol in broccoli and other cruciferous vegetables. Small human trials consistently show it raises the urinary 2-hydroxyestrone to 16-alpha-hydroxyestrone ratio and serum SHBG — a biomarker shift, not a proven health outcome. Where outcomes were measured, results disappoint: a 551-woman RCT found 150 mg/day did not improve low-grade cervical abnormalities or clear HPV, and a 1-year BRCA-carrier study found only a tiny drop in breast density. Cervical suppository and prostate trials were small and need replication. There are no controlled trials supporting the common marketing claims for acne, fat loss, menopause or 'hormone balancing'. In women on tamoxifen, DIM lowered active drug levels, which is a concern. Overall it is biologically active but clinically unproven for the things people buy it for.
Purported Benefits
✓Shift estrogen metabolite ratio
✓Hormonal acne (claimed)
✓Cruciferous-vegetable extract
✓Investigational cancer biomarker tool
Evidence by outcome
The same supplement can be well-proven for one use and unproven for another — here is the human evidence graded outcome by outcome.
Generally well tolerated short-term; the most common effect is harmless dark/amber urine, plus occasional nausea, headache or GI upset (more frequent above ~200 mg). DIM induces and competes for CYP450 enzymes, so it can lower levels of drugs cleared this way — notably it reduced active tamoxifen (endoxifen) metabolites in an RCT, and asymptomatic hyponatremia has been reported when high-dose DIM was combined with sodium-depleting diuretics. Because it alters estrogen and androgen signalling, avoid in pregnancy and breastfeeding and use caution with hormone therapy, hormone-sensitive cancers and any CYP-metabolised medication. Educational only — always check with your doctor or pharmacist before combining DIM (Diindolylmethane) with any medicine.
DIM (Diindolylmethane) is most often taken for Shift estrogen metabolite ratio, Hormonal acne (claimed), Cruciferous-vegetable extract, Investigational cancer biomarker tool. Broccoli-derived compound marketed to shift estrogen metabolism.
Does DIM (Diindolylmethane) work — what does the evidence say?
Mixed evidence. Conflicting results across studies; benefit uncertain. DIM is a compound your gut forms from indole-3-carbinol in broccoli and other cruciferous vegetables. Small human trials consistently show it raises the urinary 2-hydroxyestrone to 16-alpha-hydroxyestrone ratio and serum SHBG — a biomarker shift, not a proven health outcome. Where outcomes were measured, results disappoint: a 551-woman RCT found 150 mg/day did not improve low-grade cervical abnormalities or clear HPV, and a 1-year BRCA-carrier study found only a tiny drop in breast density. Cervical suppository and prostate trials were small and need replication. There are no controlled trials supporting the common marketing claims for acne, fat loss, menopause or 'hormone balancing'. In women on tamoxifen, DIM lowered active drug levels, which is a concern. Overall it is biologically active but clinically unproven for the things people buy it for.
What is the typical dose of DIM (Diindolylmethane)?
Most trials used 100–150 mg/day of an absorption-enhanced formulation (BioResponse-DIM); cancer studies have gone up to 900 mg/day.
Is DIM (Diindolylmethane) safe? Any cautions or side effects?
Generally well tolerated short-term; the most common effect is harmless dark/amber urine, plus occasional nausea, headache or GI upset (more frequent above ~200 mg). DIM induces and competes for CYP450 enzymes, so it can lower levels of drugs cleared this way — notably it reduced active tamoxifen (endoxifen) metabolites in an RCT, and asymptomatic hyponatremia has been reported when high-dose DIM was combined with sodium-depleting diuretics. Because it alters estrogen and androgen signalling, avoid in pregnancy and breastfeeding and use caution with hormone therapy, hormone-sensitive cancers and any CYP-metabolised medication.
How many studies support DIM (Diindolylmethane)?
NutriDex cites 8 sources for DIM (Diindolylmethane), graded "Mixed".
Cite this page
APA
Peh, D. (2026). DIM (Diindolylmethane): Benefits, Dosage, Side Effects & Evidence. NutriDex — The Supplement Research Compendium. Retrieved 16 Sept 2026, from https://nutridex.info/s/dim
BibTeX
@misc{nutridex_dim,
author = {Peh, Daryl},
title = {DIM (Diindolylmethane): Benefits, Dosage, Side Effects \& Evidence},
year = {2026},
howpublished = {NutriDex --- The Supplement Research Compendium},
url = {https://nutridex.info/s/dim},
note = {Reviewed by Dr Daryl Peh, MBBS Singapore, MMed FM. Accessed 2026-09-16}
}
For medical claims, citing the underlying primary studies linked above is preferred. NutriDex is an educational reference, not medical advice.