Indole-3-Carbinol (I3C)
Commonly used for
Nutrition
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What is it? / Overview
Indole-3-carbinol is converted to DIM and other metabolites after ingestion. While laboratory studies are compelling, human clinical evidence remains limited and supplementation should be viewed as investigational for most indications.
How is it used? / Administration
Form: Indole-3-carbinol
Typical dose studied: 200–400 mg/day
Timing: With meals
Increasing cruciferous vegetable intake remains the preferred strategy over supplementation for most healthy adults.
How well does it work? / Evidence
? Emerging / limited evidence
Who should avoid it?
Avoid with: Cancer — active or within past 12 months
Interacts with: Hormonal medications; CYP-metabolized medications — potential interactions
Already taking it? DIM and I3C generally not necessary together unless specifically recommended.
Research & references
Reed GA et al. (2006). I3C pharmacokinetics and tolerability. Cancer Epidemiology, Biomarkers & Prevention. Elgar K. (2021). Sulforaphane, DIM, I3C clinical review. Nutritional Medicine Journal. Mecca M et al. (2024). Dietary bioactive compounds in breast cancer prevention. Nutrients.
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