Melatonin guide: timing, dosage, and what it actually does
Melatonin is one of the most widely used sleep supplements, but it's also widely misunderstood — many people take it the wrong way for the wrong problem and then conclude it "doesn't work." Here's what it actually does and how to use it well.
What melatonin actually is
Melatonin is a hormone your brain naturally produces in response to darkness, signaling to your body that it's time to prepare for sleep. It's a timing signal, not a sedative — this distinction matters enormously for how and when you should take it.
When melatonin genuinely helps
- Jet lag: One of the best-supported uses — taken at the destination's bedtime, it can help shift your circadian clock to the new time zone faster.
- Shift work: Can help realign sleep timing for people working irregular or night shifts, taken at the intended sleep time.
- Delayed sleep phase (extreme night owls): Taken several hours before desired bedtime, it can gradually shift sleep onset earlier over days to weeks.
When it's less likely to help
For general, chronic insomnia unrelated to circadian timing, melatonin's evidence is weaker than its popularity suggests — it may modestly reduce the time it takes to fall asleep, but it doesn't address the underlying causes of most chronic insomnia, where approaches like cognitive behavioral therapy for insomnia (CBT-I) have stronger evidence.
Dosage: less is usually more
Timing matters as much as dose
- For general sleep onset: 30-60 minutes before your intended bedtime.
- For jet lag (traveling east, losing time): taken at the new destination's bedtime, starting a day or two before or immediately upon arrival.
- For shifting a delayed sleep phase earlier: taken several hours before your current natural sleep time, gradually moved earlier over days.
Safety notes
Melatonin is generally considered safe for short-term use in adults, but quality and labeled-dose accuracy vary significantly between over-the-counter products. It can interact with certain medications (including blood thinners and some diabetes medications), so checking with a doctor or pharmacist is worthwhile if you're on other medication or considering regular, long-term use — especially for children, where dosing guidance differs.
Frequently asked questions
Can I become dependent on melatonin?
Unlike sedative sleep medications, melatonin isn't considered habit-forming in the same way, but relying on it long-term without addressing underlying sleep hygiene or circadian issues isn't a substitute for fixing the root cause.
Why didn't melatonin work for me?
The most common reasons are: too high a dose (paradoxically less effective), wrong timing for your specific issue, or an underlying cause (like poor sleep hygiene or an undiagnosed sleep disorder) that melatonin alone can't fix.
Is melatonin safe for children?
It's used in some pediatric cases under medical guidance, but dosing and appropriateness should be discussed with a pediatrician rather than used independently, since children's circadian systems and appropriate doses differ from adults'.