Supplements
Melatonin Is a Hormone and Every Country Treats It Differently
In some places it needs a prescription and in others it sits beside the chewing gum. That inconsistency tells you more about regulation than about the molecule, and both matter for how you should use it.
There is a settled way of talking about melatonin regulation, timing and dose. It is worth asking how much of it survives contact with the detail.
The argument in brief
- It signals darkness rather than acting as a sedative.
- Timing relative to your own rhythm affects the result more than the amount.
- Legal status varies widely, and content of unregulated products has been found inconsistent.
What the hormone does
Melatonin is produced by a small gland in the brain and rises in the evening as light fades, peaking during the night. Its role is to signal biological night to the rest of the body rather than to switch off consciousness. This makes it a timing signal, closer in function to a clock hand than to a sedative or a sleeping tablet.
Light exposure suppresses its production, which is the mechanism behind advice about screens and bright light late in the evening. Understanding it as a signal rather than a knockout explains why people who expect drowsiness are often disappointed.
Why timing matters more than quantity
Taking it a short time before the desired bedtime and taking it several hours earlier produce different effects on your rhythm. Shifting a body clock earlier generally requires taking it in advance of the natural rise, which is not when most people take it. This is why it has clearer support for circadian problems such as jet lag and shift patterns than for ordinary insomnia.
At the dose actually studied, a person whose rhythm is already aligned and who simply cannot fall asleep is treating a different problem with a timing signal. Sleep trials of it generally show a modest reduction in the time taken to fall asleep rather than a transformation.
The regulatory split
In some countries melatonin is a prescription medicine, assessed for quality and approved for particular indications and age groups. In others it is sold as a food supplement, in gummies and sprays, without any efficacy assessment before it reaches shelves. The same molecule is therefore subject to entirely different quality requirements depending on where it is bought.
On the label, analyses of supplement-market products in more than one country have found content differing considerably from the label, in both directions. Some samples in those analyses also contained serotonin, which is not a substance anyone intends to take unlabelled.
Dose inflation and what it does
Products in unregulated markets are often sold at amounts far above what the body produces overnight. Higher amounts extend how long the signal persists, which can leave people groggy the following morning. More is not obviously better for a signalling molecule, because the receptor system responds to presence rather than to magnitude.
This is a case where dose questions belong with a doctor or pharmacist rather than with a product page.
This article names no dose deliberately, because the right one depends on the person, the purpose and the country.
Children, pregnancy and medicines
Use in children has grown quickly, and it is a decision for a paediatrician rather than a purchase, particularly where sleep problems are longstanding. Gummy formats resemble sweets, and unintentional ingestion by young children has become a recognised problem for poison centres.
It has not been well studied in pregnancy or breastfeeding, which means the honest position is unknown rather than safe. Interactions include anticoagulants, some blood pressure medicines, anticonvulsants and sedatives, and it is processed by liver enzymes many drugs use. Anyone taking regular medication should check with a pharmacist before adding it and should never alter a prescription because of it.
Never stop or alter a treatment a clinician has prescribed on the strength of something you have read.
What to fix before reaching for it
Persistent insomnia responds best to a structured behavioural approach, which has the strongest evidence base of any insomnia treatment. Consistent wake times, morning light exposure and reducing evening light all act on the same clock melatonin signals to. Alcohol shortens the time to fall asleep and fragments the second half of the night, which is a common hidden cause.
Sleep that is unrefreshing despite adequate hours, loud snoring, or breathing pauses noticed by a partner point to a sleep disorder needing assessment. Sleep itself is one of the best-supported health behaviours there is, which makes it worth treating properly rather than patching.
The takeaway
It tells your body it is night; it does not knock you out. Where it is sold as a supplement, what is in the bottle has repeatedly failed to match the label.
An extraordinary mechanism needs better evidence than testimonials, and usually has less.
Questions readers ask
Is it addictive?
It does not produce the dependence pattern associated with sedative medicines. Habit and expectation can still make stopping feel difficult, which is a different phenomenon and worth discussing with a clinician.
Does it work for jet lag?
This is where the evidence is comparatively better, and timing relative to the destination clock is what makes the difference. Guidance differs by direction of travel, so it is worth reading properly before a trip.
