Pilot study: effect of 3,3'-diindolylmethane supplements on urinary hormone metabolites in postmenopausal women with a history of early-stage breast cancer.
Level 2 - randomized trial
Individual randomized controlled trial
PubMed 15623462 · doi:10.1207/s15327914nc5002_5
What was done
In a randomized, placebo-controlled pilot trial, postmenopausal women aged 50–70 years with a history of early-stage breast cancer received either daily absorbable 3,3'-diindolylmethane (DIM, 108 mg/day; n=10) or a placebo (n=9) for 30 days. First morning urine samples collected at baseline and 31 days after intervention were analyzed for urinary hormone metabolites, including 2-hydroxyestrone (2-OHE1), 16-alpha hydroxyestrone (16alpha-OHE1), DIM, estrone (E1), estradiol (E2), estriol (E3), 6beta-hydroxycortisol (6beta-OHC), and cortisol.
What was found
Nineteen women completed the study. Relative to placebo, the DIM-treated group showed statistically significant increases in urinary levels of 2-OHE1 (P = 0.020), DIM (P = 0.045), and cortisol (P = 0.039). The 2-OHE1/16alpha-OHE1 ratio showed a non-significant 47% increase from 1.46 to 2.14 (P = 0.059). Values for E1, E2, E3, and 6beta-OHC were not reported in the abstract.
Why it matters
This pilot study demonstrates that oral DIM supplementation can increase urinary 2-hydroxylation of estrogen in postmenopausal breast cancer survivors, a metabolic pathway hypothesized to be protective.
Limits
The sample size was very small (n=19), the intervention duration was brief (30 days), and the study evaluated surrogate urinary biomarkers rather than clinical recurrence or long-term health outcomes.
Cited by
- context Diindolylmethane (DIM) derived from cruciferous vegetables acts as a natural aromatase inhibitor.