Legacy AI grade · Sources dated 2026-07-25. Not expert reviewed. Coverage is limited to the listed sources. About the new summary workflow

Diindolylmethane (DIM) for Acne

Verdict: Taiwan Regulatory Restriction

Across 4 PubMed studies, the evidence for Diindolylmethane (DIM) in Acne grades Tier U — unverified / insufficient.

U ⚫ U Unverified Taiwan Regulatory Restriction

🔬Why this grade7-layer evidence engine

⚖️

Scoring transparency

All scores computed by a 7-layer evidence engine — fully auditable
Raw score 0.44
D
C
B
A
S
← counter-evidence / ineffectiveeffective / strong evidence →
Final grade
U · Taiwan Regulatory Restriction
Confidence
77%
Broadly consistent
Evidence level
E7
Single small RCT

How strongly each layer supports this effect

lower = less supportive
L11 AI re-checkIndependent read
0.20
L2 PubMedPrimary literature
0.40
L1 ExamineGlobal benchmark
0.50
L3 MechanismPlausibility
0.50
L5 Clinical bodiesAuthoritative stance
0.50
Against Mixed Supports
▸View the full decision path (audit trail)
  1. compute_raw_score — 加權公式: L2×0.30 + L3×0.25 + L5×0.25 + L11×0.10 + L1×0.10 = 0.44
  2. tier_from_score — 依分數區間映射至 tier letter
  3. apply_hec_rules — 無高階證據可裁決
  4. tier_strict_requirement_check — Tier 條件達標,未降階
  5. detect_disputes — 偵測到 0 個 hard + 0 個 soft dispute
  6. decide_status — 依 tier + dispute 結果決定 status

📄PubMed studies (4)L2 · primary research & systematic reviews

DIM Inhibits Multispecies Biofilm Formation by Acne-Causing Bacteria and C. albicans
PMID: 35107361 2022 Cross-sectional
Finding: DIM at 0.1 mM significantly inhibited planktonic growth and biofilm formation by C. acnes (P<0.05); also blocked S. aureus + C. albicans co-biofilm and downregulated biofilm-related genes (lipase, hyaluronate lyase).
🟠 Limited quality Academic
View on PubMed
Impact of DIM on urinary estrogen profile of premenopausal women
PMID: 39578798 2024 Cohort n = 909
Finding: DIM users showed significant differences in nearly all urinary estrogen metabolites (P<0.001) vs non-users; 2-OHE1:16-OHE1 ratio significantly increased in both whole-group and pre/post analyses, consistent with shift toward less-estrogenic metabolism. No acne or skin endpoint measured.
🟠 Limited quality ⚠️ Industry-funded
View on PubMed
DIM modulates estrogen metabolism in thyroid proliferative disease patients
PMID: 21254914 2011 RCT (open-label)
Finding: 2-OHE1:16-OHE1 ratio significantly increased (P<0.05), consistent with antiestrogenic activity. No skin/acne endpoints.
🟠 Limited quality Government
View on PubMed
DIM is a strong androgen receptor antagonist in human prostate cancer cells
PMID: 12665522 2003 Cross-sectional
Finding: DIM is a strong competitive inhibitor of DHT-AR binding; blocks AR nuclear translocation and PSA transcription; functions as bifunctional hormone disrupter.
🟠 Limited quality Government
View on PubMed

🏛️Regulatory & authoritative positionsL4/L5 · FDA / EMA / NIH ODS / Cochrane / Mayo …

L4a US FDA
Cautious
3,3'-DIINDOLYLMETHANE source↗
L4b EU EFSA
Against
Purified, synthetic 3,3'-diindolylmethane powder in supplement form is considered novel... 3,3'-diindolylmethane powder has been classified as a 'Novel Food' because it had not been consumed to a significant degree by humans in the UK or the European Union before May 15, 1997. It has not been granted authorization for sale as a food supplement. source↗
L4e WHO
Supportive
3,3'-Diindolylmethane (DIM). CAS 1968-05-4. Source materials: Brassica oleracea var. botrytis (cauliflower), var. capitata (cabbage), var. gemmifera (Brussels sprouts), var. italica (broccoli) — whole plant. Schedule 1, Item 2 (isolate). Approved Use(s) or Purpose(s): Source of/Provides antioxidants that help fight/protect cells against/reduce the oxidative effects of (or oxidative damage cause… source↗
L5a NIH Office of Dietary Supplements
Cautious
✓PMID 100% verifiedevery citation checked via NCBI Entrez
🔬4 PubMed studiesindependently re-checked by multiple sub-agents
engine_version: v1.0 claim_id: CLM-COND-acne-INT-diindolylmethane-001 繁體中文版 →