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Melatonin Dosage by Weight: What the Research Actually Says

Your weight, your age group, and the amounts research used against the amounts stores sell.

-starting range used in adult research, for any weight
-of melatonin labels in the NIH database sell more than that
-most common labelled amount per serving

Is melatonin dosed by body weight?

For adults, no. The clinical trials behind melatonin did not scale the amount to body weight. They tested fixed amounts against placebo, and the lowest ones worked: in the placebo-controlled MIT crossover trial of older adults, 0.3 mg raised blood melatonin into the range the body produces on its own at night and was the amount that worked best, 1 to 3 mg were the usual trial amounts, and higher amounts were not more effective in head-to-head comparisons but did last longer into the morning. Weight-based dosing exists in some paediatric clinical practice, which is why the question comes up, and that is a clinician's decision rather than a chart to read off.

What does change the amount is age (melatonin tends to stay in the blood longer in older adults, and a systematic review recommended the lowest immediate-release amount that mimics the body's own night-time level), timing (30 to 60 minutes before the bedtime you want), and what else you take. The calculator above gives the research range for your age group and shows how it compares with what is sold.

What the shelves sell

We counted 2,674 melatonin labels in the NIH Dietary Supplement Label Database. The median label is 3 mg, 34% are 5 mg or more, and only 19% are 1 mg or under. Full counts, charts and the download are on the melatonin label data page.

Melatonin amounts compared

Amount What it corresponds to
0.3 mg About what the pineal gland releases at night; the amount that restored night-time blood levels in older adults in the MIT trials
0.5 to 1 mg Low end of trial amounts; the amount used in most jet lag studies alongside 5 mg
1 to 3 mg The usual range in sleep-onset trials; 3 mg is the most common label amount in the NIH database
5 mg Common on shelves; more morning carry-over, no advantage over lower amounts in comparisons
10 mg and above 13% of labels; well above any amount needed to reach night-time blood levels

Children

Paediatric melatonin is prescribed case by case, often by weight or age and at the lowest amount that works. The research does not support choosing a child's amount from a chart, and US poison-control calls about children and melatonin rose by more than five times between 2012 and 2021, mostly from unintentional ingestion. Ask a paediatrician.

Sources

  1. Zhdanova IV, Wurtman RJ, Regan MM, Taylor JA, Shi JP, Leclair OU. Melatonin treatment for age-related insomnia. Journal of Clinical Endocrinology and Metabolism. 2001;86(10):4727-4730. doi.org/10.1210/jcem.86.10.7901
  2. Vural EMS, van Munster BC, de Rooij SE. Optimal dosages for melatonin supplementation therapy in older adults: a systematic review of current literature. Drugs and Aging. 2014;31(6):441-451. doi.org/10.1007/s40266-014-0178-0
  3. Herxheimer A, Petrie KJ. Melatonin for the prevention and treatment of jet lag. Cochrane Database of Systematic Reviews. 2002;(2):CD001520. doi.org/10.1002/14651858.CD001520
  4. Lelak K, Vohra V, Neuman MI, Toce MS, Sethuraman U. Pediatric melatonin ingestions, United States, 2012-2021. MMWR. 2022;71(22):725-729. doi.org/10.15585/mmwr.mm7122a1
  5. National Institutes of Health, Office of Dietary Supplements. Dietary Supplement Label Database, API v9. Accessed 1 October 2026.

These studies looked at melatonin as an ingredient in volunteers and at labels in a public database. None of them tested a Veluna product; this page relates to individual ingredients and is not the Veluna product.

Common questions

How much melatonin should I take for my weight?

Adult research did not scale melatonin to body weight, so there is no weight-based adult dose. Trials used fixed amounts, and 0.3 to 1 mg was enough to reach night-time blood levels. Talk to a clinician about your own situation.

Is 5 mg of melatonin a lot?

It is above the amounts used in most trials, although it is one of the most common amounts on shelves: 34% of labels in the NIH database are 5 mg or more. Higher amounts were not more effective in comparisons and last longer into the morning.

Does melatonin dosage change with age?

Reviews of older adults suggest starting at the low end, 0.3 to 1 mg, because melatonin clears more slowly after 65. For children, paediatric use is decided by a clinician.

When should I take melatonin?

In trials, 30 to 60 minutes before the intended bedtime. Taken at the wrong time of day it can shift the body clock the wrong way.

Timing beats the numberThe evening routine around the capsule matters more than the milligrams. Find your version in two minutes.

Find your evening routine

This calculator is for general education and planning. It is not medical advice and does not diagnose, treat, cure or prevent any condition. Talk to a healthcare professional about your own situation, especially if you are pregnant, nursing, take medication or have a medical condition.