✓ No active regulatory warningsFDA MedWatch, EMA EudraVigilance, WHO VigiBase, WADA Prohibited List · 2026-05-29
📰Read the full DIM evidence review on GMJ News →Complete clinical article, references and updates on news.gmj.ge. This page is the structured safety summary.⚠ Evidence is surrogate markers (estrogen metabolites) only — no outcome data [2]
⚠ Patient on tamoxifen/AI/HRT — DIM alters estrogen metabolism [1]
⚠ Bioenhanced DIM required — regular is poorly absorbed [1]
⚠ CYP1A2 induction — caffeine and other CYP1A2 substrates [1]
ℹ️ Not obtained from food. Not applicable — this is not obtained from food in meaningful amounts; supplementation is the practical route.
🔬 Lab interpreter
Recommended test
Urinary 2-OHE1:16α-OHE1 ratio
Urinary 2-OHE1:16α-OHE1 ratio
Reference range / target
Increased (favorable shift)
Increased (favorable shift)
Surrogate marker [1].
Full lab monitoring ↓⚕ For professionals — confirm ranges against your local laboratory.
Clinical verdict
DIM shifts estrogen metabolism (2:16α ratio) — this is confirmed. Whether this translates to clinical outcomes (cancer prevention, PMS relief, acne) is UNPROVEN. Evidence is almost entirely surrogate markers. Bioenhanced DIM is required for absorption. AVOID with hormonal therapies. The marketing far exceeds the evidence [1] [2].
1 How much do I need?
👤 Adults: Specific dosage data under clinical review
👴 Elderly: Specific dosage data under clinical review
🤰 Pregnancy: See guidance
AVOID — alters estrogen metabolism [1].
👦 Pediatric: See guidance
Not appropriate [1].
🏃 Athletes: Standard dose
⚖️ Obesity: Standard dose
Fat-soluble compounds may require dose adjustment in obesity.
🩺 Renal: Consult specialist
Dose adjustment may be needed in renal impairment.
🌱 Vegan: Standard dose
How to take
🍽 Timing: With food [1].
💊 With food: With fat for absorption [1].
🚫 Avoid: Hormonal therapies. Pregnancy. OCPs without physician guidance [1].
2 Which form?
| Form | Bioavailability | Vegan | Cost |
|---|---|---|---|
| ['BioResponse DIM (enhanced absorption)', 'preferred', 'Microencapsulated for absorption. 100–200 mg/day. Most studied [2].'] | Standard | Check label | |
| ['Regular DIM', 'common', 'Poor absorption without enhancement [1].'] | Standard | Check label | |
| ['I3C (indole-3-carbinol)', '', 'Precursor to DIM. Converted in stomach. Less stable/predictable than direct DIM [1].'] | Standard | Check label |
3 Common questions
Does DIM balance estrogen? ▼
Is DIM better than I3C? ▼
DIM is the active metabolite and is more stable/predictable than I3C (which requires acid conversion and is unstable). Bioenhanced DIM is preferred over I3C [1].
Can men take DIM? ▼
It's marketed to men as an 'anti-estrogen.' DIM shifts estrogen metabolism but there's minimal clinical evidence for benefit in men beyond prostate PSA data [2].
4 Clinical evidence
Strong
2:16α estrogen metabolite ratio shift: confirmed in human studies with DIM supplementation [1]. HIGH
Moderate
Cervical dysplasia (CIN): some positive data for I3C/DIM in regression of CIN I [2]. 2:16α ratio improvement: consistent in supplementation studies [1]. Prostate: PSA reduction in some small studies [2]. MODERATE
Insufficient
5 Safety, toxicity & adverse events
Relative
⚠ Hormone-sensitive conditions — alters estrogen metabolism
⚠ May induce CYP1A2/CYP3A4 — affects some drug levels
⚠ Can darken/change urine colour (benign)
⚠ Pregnancy and lactation — avoid
🚩 Red flags
● Patient on tamoxifen/AI/HRT + DIM — hormonal interference [1]
6 Interactions
Drug interactions
Tamoxifen / aromatase inhibitors / HRT Major
Mechanism: DIM alters estrogen metabolism. May interfere with hormonal therapy mechanism. [1]
Effect: Uncertain — may enhance or diminish drug effect. [1]
Action: Avoid without oncologist/endocrinologist guidance [1].
CYP1A2 substrates (caffeine, theophylline) Moderate
Mechanism: DIM induces CYP1A2. [1]
Effect: Reduced drug levels. [1]
Action: Monitor [1].
Supplement synergies
Calcium D-Glucarate · 500–1,500 mg
Supports estrogen excretion via glucuronidation [1].
Supports estrogen excretion via glucuronidation [1].
7 Regulatory
United States: Dietary supplement [1].
8 US supplement products
1
on-market products containing DIM (NIH DSLD)
Brands carrying DIM (1)
Click a brand to see its DIM products.
9 Frequently paired with
10 Cite this page
Vancouver: Pkhakadze G. DIM — safety profile [Internet]. Tbilisi: PHIG; 2026 [cited 2026 Jul 17]. Available from: https://supplement.ge/ingredients/dim/
APA 7th: Pkhakadze, G. (2026). DIM — Safety profile. Public Health Institute of Georgia. https://supplement.ge/ingredients/dim/
📋 Editorial information
Author: Prof. G. Pkhakadze, MD, MPH, PhD
Institution: Public Health Institute of Georgia (PHIG)
Affiliation: David Tvildiani Medical University (DTMU)
First published: January 2026
Last reviewed: 2026-05-29
Next review: January 2027
References: 2 cited sources
COI: SupplementIndex receives no funding from supplement manufacturers. All content independently authored by PHIG.
Process: Systematic literature review
📄 License & reuse
Published under Creative Commons Attribution 4.0 International (CC BY 4.0). You may share and adapt for any purpose with attribution.
Pkhakadze G. "DIM — Safety Profile." SupplementIndex, PHIG, 2026. https://supplement.ge/ingredients/dim/ CC BY 4.0.
GP
Prof. G. Pkhakadze, MD, MPH, PhD
Professor of Public Health · Head of Department, DTMU
Editor-in-Chief, Georgian Medical Journal (ISSN 3088-4322)
Chair, Public Health Institute of Georgia · UEMS Public Health Section
Educational and public health purposes. CC BY 4.0. Consult your healthcare provider before starting any supplement. Corrections: info@accreditation.ge. Publisher: PHIG