Melatonin: what it is and how much people take
Melatonin is a hormone the brain makes in response to darkness. Most supplements are synthetic. Studies have looked at jet lag, delayed sleep timing and anxiety before surgery; there is not enough evidence for long-term insomnia. EU health claims are based on 0.5 milligrams for jet lag and 1 milligram for falling asleep faster. Short-term side effects can include headache, dizziness, nausea and sleepiness. In the UK it is prescription only.
General information, not medical advice. Check with a doctor or pharmacist before taking a supplement, especially if you are pregnant or breastfeeding, take any medicine, or are under 18.
How much people take
| What studies looked at | Studies have looked at jet lag, delayed sleep timing and anxiety before surgery; there is not enough evidence for long-term insomnia. |
|---|---|
| Other guidance | EU health claims are based on 0.5 milligrams for jet lag and 1 milligram for falling asleep faster. |
| Official upper limit | None set |
Cautions and interactions
- Short-term side effects can include headache, dizziness, nausea and sleepiness.
- It may interact with blood thinners and epilepsy medicines.
- In the UK it is prescription only.
- Tests have found many melatonin gummies hold a different amount from the label.
Dose questions
Quick answers
- What is melatonin?
- Melatonin is a hormone the brain makes in response to darkness. Most supplements are synthetic.
- What has melatonin been studied for?
- Studies have looked at jet lag, delayed sleep timing and anxiety before surgery; there is not enough evidence for long-term insomnia.
- Is there a limit for melatonin?
- There is no official upper limit. EU health claims are based on 0.5 milligrams for jet lag and 1 milligram for falling asleep faster.
- Is melatonin safe?
- Short-term side effects can include headache, dizziness, nausea and sleepiness. It may interact with blood thinners and epilepsy medicines. In the UK it is prescription only. Tests have found many melatonin gummies hold a different amount from the label.
Sources
- NCCIH (US National Institutes of Health)
https://www.nccih.nih.gov/health/melatonin-what-you-need-to-know
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