Walk into any American pharmacy and you'll find shelves of melatonin gummies, sprays and tablets. Mention it to a friend in the UK and they'll probably say they bought some on holiday, or that their doctor prescribed it. It's become the go-to "natural" sleep aid. But if you're over 40 and struggling with sleep, is it actually the right choice?
Here's what melatonin really does, where it helps, where it doesn't, and what to think about before you try it.
What Melatonin Actually Does
Melatonin is a hormone your brain makes when it gets dark. It's best thought of as a timing signal, not a sleeping pill. It tells your body "it's night now, start winding down", but it doesn't knock you out the way a sedative does.
That's an important difference. If your problem is that your body clock is out of sync, melatonin can help. If your problem is a racing mind, waking at 3am, or stress, a timing signal on its own often isn't enough.
Why It's Different After 40
Our bodies tend to make less melatonin as we get older, and the night-time peak gets flatter. That's one reason sleep often becomes lighter and more broken in our 40s and 50s, alongside changes in stress hormones, body temperature and (for many women) menopause.
So it seems logical to top it up. And for some people, especially those over 55, that can help. But a smaller natural supply doesn't automatically mean a supplement is the answer.
What the Research Says
- It works best for timing problems: jet lag, shift work, or a body clock that runs late. This is where the evidence is strongest.
- For everyday insomnia, the effect is modest. Reviews of the research suggest people fall asleep slightly faster on average, often by only a few minutes, and sleep a little longer. Helpful for some, underwhelming for many.
- More isn't better. Low doses (around 0.5–2 mg) often work as well as high ones, and higher doses are more likely to leave you groggy the next morning.
UK vs US: The Rules Are Very Different
In the UK, melatonin is a prescription-only medicine. A doctor can prescribe a slow-release version for short-term insomnia in people aged 55 and over, usually for a few weeks. Buying it online from abroad means you can't be sure what you're getting.
In the US, it's sold freely as a dietary supplement, so quality varies. A Canadian study that tested 31 melatonin supplements found the actual amount ranged from far less to several times more than the label said. If you do buy it, look for a reputable brand with independent testing.
Side Effects and Who Should Be Careful
Melatonin is generally well tolerated for short-term use, but some people get:
- Morning grogginess or a "hangover" feeling
- Headaches, dizziness or nausea
- Vivid dreams
Talk to your doctor or pharmacist first if you take blood thinners, sedatives or sleeping tablets, blood pressure or diabetes medication, or certain antidepressants, or if you have epilepsy or an autoimmune condition. And don't drive or use machinery if it leaves you drowsy.
What About Melatonin-Free Options?
Because melatonin is mainly a timing signal, many people over 40 find they need something that helps them relax and switch off instead. That's where melatonin-free options come in. Ingredients such as magnesium, L-theanine, valerian and lemon balm are designed to support calm and relaxation rather than reset your body clock, and many people prefer them because they're less likely to cause next-day grogginess.
One example is Sleep Revive, which combines all four. I've looked closely at what's in it, the real UK and US prices and the guarantee small print in my Sleep Revive review.
What I'd Try First
Before reaching for any supplement, these habits give your own melatonin the best chance:
- Get daylight in the morning. Ten to twenty minutes outside soon after waking sets your body clock for the night ahead.
- Dim the lights after 8pm and keep screens on night mode, or better, out of the bedroom.
- Keep the same wake-up time every day, even at weekends.
- Watch late caffeine and alcohol. Both break up sleep in the second half of the night.
If you've done the basics and still struggle, it's reasonable to try a gentle supplement, melatonin or melatonin-free, for a few weeks and see how you feel. And if poor sleep has gone on for months, or you snore heavily or wake up gasping, speak to your GP. Persistent insomnia and sleep apnoea both need proper attention.
This article is for general information only and isn't medical advice. Always check with your doctor or pharmacist before starting a new supplement.
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