Research

Hormonal

Low endogenous melatonin production (defined as urinary 6-SMT ≤8 μg/night) is NOT a useful predictor of response to melatonin therapy in insomnia patients.

You do not need to get your melatonin levels tested to decide if melatonin might help your sleep. The study shows that low melatonin levels do not predict whether you will respond to melatonin therapy. Instead, being over 65 is a better indicator of potential benefit.

GoodRefutesHIGH confidence
Low melatonin production regardless of age is not useful in predicting responses to melatonin therapy in insomnia.
Alan Wade et al. · BMC Medicine · 2010

Why this rating

Based on the same high-quality RCT, specifically the subgroup analysis of low excretors.

Source

Nightly treatment of primary insomnia with prolonged release melatonin for 6 months: a randomized placebo controlled trial on age and endogenous melatonin as predictors of efficacy and safety

Alan Wade et al. · BMC Medicine · 2010

DOI 10.1186/1741-7015-8-51

rct · n=791Cited 177×
Read the paper
DOI resolved against Crossref · corpus check 2026-06-10

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