Hormonal/Women

Indole-3-carbinol

Cruciferous vegetable compound that may shift estrogen metabolism and support cervical health in women.

score

evidence

Caution

risk

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Use with caution

This supplement may interact with medications, medical conditions or sensitive populations. Review safety before use.

Overview

Forms

Safety

Stack

Quick Take

Only worth considering for specific estrogen-related concerns under medical supervision; not a general wellness supplement.

Indole-3-carbinol (I3C) is a compound formed from glucosinolates in cruciferous vegetables such as broccoli, cabbage, Brussels sprouts, and cauliflower when they are chopped or chewed. In the stomach it converts to DIM and related compounds that activate AhR and change estrogen-metabolizing enzymes. The best-supported effects are a shift in urinary estrogen metabolites, possible improvement in cervical dysplasia, and modest changes in breast-cell biomarkers. It is most relevant for women being monitored for HPV-related or hormone-related cervical concerns.

Potential benefits

Shifts estrogen metabolites

May improve cervical dysplasia

May reduce breast cell proliferatio

Protocol

Amount

200-400 mg

Frequency

Once daily

When

With food to reduce stomach upset; any time of day is fine.

Onset Time

2-4 weeks for metabolite changes; clinical benefit, if any, is slower.

Who Should Consider

Women with cervical dysplasia or abnormal Pap results

Women with HPV-related cervical changes

Women being monitored for estrogen-related concerns

Women seeking a short-term estrogen shift

How It Works

After ingestion, I3C condenses in gastric acid into DIM and other oligomers that activate the aryl hydrocarbon receptor and induce CYP1A1/CYP1A2. This shifts estrogen metabolism toward 2-hydroxylation and can alter downstream signaling in hormone-responsive tissues.

Updated 5/19/2026