NutriStack
DIM and Melatonin, a caution.
DIM is a documented CYP1A2 inducer (shown in cultured human liver slices via the AhR pathway), and melatonin is primarily metabolized by CYP1A2. Regular DIM use can speed melatonin breakdown, potentially blunting the sleep-onset effect of an exogenous melatonin dose. Because this is an enzyme-induction effect that builds over days, simply spacing the two doses apart does not resolve it: induction is a systemic, sustained change in metabolism rather than a moment-of-contact conflict.
One pair, every claim cited. The two substances, the type, the mechanism, the recommendation, and the primary literature.
Same shape as the other 1,729 pairs in the public database.
From the interaction database
What the row says.
Every entry follows the same shape: what is happening, the mechanism, the recommendation, and the primary literature.
At a glance
- Pair type
- Caution
- Evidence (highest tier)
- Emerging
- Source citations
- 3 sources
- Stack Score effect
- −5 to your Stack Score (per scored caution row).
- Scope
- Supplement × Supplement
- Last verified
- May 30, 2026
Caution · Emerging evidence
Caution
What is happening. DIM is a documented CYP1A2 inducer (shown in cultured human liver slices via the AhR pathway), and melatonin is primarily metabolized by CYP1A2. Regular DIM use can speed melatonin breakdown, potentially blunting the sleep-onset effect of an exogenous melatonin dose. Because this is an enzyme-induction effect that builds over days, simply spacing the two doses apart does not resolve it: induction is a systemic, sustained change in metabolism rather than a moment-of-contact conflict.
Mechanism. DIM (3,3'-diindolylmethane) activates the aryl hydrocarbon receptor and induces hepatic CYP1A2, the same high-affinity enzyme that carries out the main metabolic step for melatonin (6-hydroxylation to 6-hydroxymelatonin). Sustained CYP1A2 induction increases melatonin clearance, so a given dose of supplemental melatonin can produce lower blood levels and a shorter duration of effect.
Recommendation. If you take DIM daily and use melatonin for sleep, do not expect dose separation to fix reduced melatonin effect: the issue is faster clearance, not timing of contact. If your usual melatonin dose (commonly 0.5 to 3 mg at night) seems less effective after starting daily DIM, discuss a modest dose adjustment with a clinician rather than escalating on your own. Allow 1 to 2 weeks after starting or stopping DIM for the metabolic effect to stabilize before judging melatonin's effect.
Minimum separation. Dose separation does not mitigate this enzyme-induction effect; spacing the two apart provides no benefit
Sources (3)
- Lake BG et al. 3,3'-Diindolylmethane induces CYP1A2 in cultured precision-cut human liver slices. Xenobiotica. 1998;28(8):803-11. PMID 9741959
- Ma X et al. Metabolism of melatonin by human cytochromes p450. Drug Metab Dispos. 2005;33(4):489-94. PMID 15616152
- Skene DJ et al. Contribution of CYP1A2 in the hepatic metabolism of melatonin: studies with isolated microsomal preparations and liver slices. J Pineal Res. 2001;31(4):333-42. PMID 11703563
Stack Score
How this pair moves the number.
Effect on the composite score
If both DIM and Melatonin are in the same stack, this pair applies −5 to your Stack Score (per scored caution row).
The full algorithm, the clamping rules, and four worked stacks are documented at /methodology/stack-score.
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