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Melatonin is nature's way of saying "bedtime" - but modern life loves to interrupt. From scrolling to street lights, discover what's messing with your sleep hormone and how to get your natural rhythm back on track for the kind of deep, restorative rest you deserve.
6 Min Read | By Nat Took
Last Modified 17 October 2025 First Added 21 July 2020
Review for Accuracy by Dr Jason Ellis
Melatonin is often called the “sleep hormone”. This natural timekeeper does more than make you drowsy; it helps coordinate your entire sleep-wake cycle, working behind the scenes to prepare your body for rest. But here’s the thing: our always-on world keeps getting in the way. We’ll explore the fascinating science of how melatonin really works, uncover the unexpected things that throw it off course (spoiler: it’s not just your phone), and share both natural strategies and supplement wisdom to help you support your body’s own sleep chemistry.
Melatonin is a naturally occurring hormone produced mainly by the pineal gland – a small, pea-shaped structure deep within the brain (it’s secreted in response to darkness and inhibited by light). It works hard by helping regulate your circadian rhythm – the internal clock that tells your body when it’s time to sleep and wake up. Your melatonin levels naturally rise in the evening as light fades, helping you feel drowsy, and they drop again in the morning as daylight returns.
Melatonin’s release is closely tied to light and darkness – it’s your body’s natural cue that night has arrived. As the sun sets and daylight decreases, your eyes detect the drop in light and send a signal to the brain’s pineal gland to begin releasing melatonin. This rise in melatonin acts like a biological “dimmer switch,” gently slowing your heart rate, lowering your body temperature, and helping your mind relax – all signals that prepare you for sleep. It doesn’t put you to sleep instantly, but rather creates the right internal conditions for sleep to come naturally.
On the other hand, exposure to bright light, especially from screens or overhead lighting in the evening, suppresses melatonin production, keeping your body in “daytime mode” and making it harder to drift off. This delicate rhythm is what keeps your sleep–wake cycle aligned with natural day and light patterns.
Our sleep naturally follows the rhythm of day and night – but modern life has other ideas. Constant light, endless notifications, and that “just one more episode” mentality can throw everything off balance. Blue light from screens and LED bulbs might be the main culprit, but it’s far from the only thing interfering with your melatonin. Want to give your natural sleep cycle the support it deserves? Here’s what actually works:
1. Reduce blue light exposure in the evening: Light from phones, tablets, and TVs tricks your brain into thinking it’s still daytime, suppressing melatonin production. Dimming lights and switching off screens at least an hour before bed helps your body recognise that it’s time to wind down.
2. Increase your exposure to natural daylight: Getting outside during the day, even for a short walk, helps regulate your internal body clock. Natural light exposure in the morning boosts alertness and ensures melatonin production kicks in naturally as evening approaches.
3. Reduce your caffeine intake later in the day: Caffeine blocks the receptors in your brain that make you feel sleepy, delaying melatonin’s effects. Avoiding coffee, tea, and energy drinks in the afternoon can help your body produce melatonin at the right time.
4. Have consistent bed and waking times: Going to bed and waking up at the same time each day reinforces your circadian rhythm. A consistent routine helps your body learn when to release melatonin and when to stop, making it easier to fall and stay asleep. Use our Sleep Calculator to find out the perfect bedtime and wake-up time for you.
5. Minimise noise and light in the bedroom: A dark, quiet room sends a clear signal to your brain that it’s night-time. Using blackout curtains or an eye mask and blocking out noise helps maintain melatonin production through the night for deeper, more restful sleep.
Dr Bay Kelly offers their advice on how to naturally support melatonin production:
“Melatonin is produced by transforming an amino acid called tryptophan, meaning that dietary factors can affect melatonin production. Tryptophan can be found in foods such as chicken, dairy products, eggs, spinach, nuts, seeds and salmon. It’s also important to know that in order for your body to produce sufficient amounts of melatonin from tryptophan, sufficient amounts of zinc, B6 and magnesium are needed.”
Read our edit of the best foods that help you sleep.
If you’re struggling to fall asleep or stay asleep, melatonin supplements might seem like an easy solution to help reset your body clock. In the UK, melatonin is available only on prescription, typically for short-term use and most often to manage sleep disruption caused by jet lag or shift work.
Melatonin supplements work by mimicking the hormone your body naturally produces at night, helping signal that it’s time to rest. While some studies suggest it can be effective in improving sleep onset and regulating the body clock, others find little to no benefit, and results can vary widely from person to person. According to Dr Kelly, doses between 1–5 mg have shown promise in some studies for those whose sleep is affected by irregular schedules, such as travellers or night-shift workers. However, for long-term sleep difficulties, it’s best to speak with your GP, as there may be underlying causes that need a more tailored approach than supplements alone.
While our bodies naturally produce melatonin for good reason, synthetic supplements are a bit more of a mystery. The good news? Research shows melatonin supplements work better than a placebo for several sleep struggles – helping you fall asleep faster, sleep longer, and get better quality rest overall.
Here’s when melatonin supplements have proven particularly helpful:
The amount of melatonin you need depends on why you’re taking it and how your body responds – there’s no one-size-fits-all answer here. Research suggests that less is often more: typically, between 1 and 5 mg is enough to support sleep for most adults. Taking extra won’t knock you out faster – in fact, it might leave you feeling foggy the next morning (not exactly the fresh start you were after).
Because melatonin is a hormone, it’s smart to start with the lowest dose that works for you. In the UK, you’ll need a prescription for melatonin, which means your GP will help work out the right dosage and timing for your specific sleep needs – taking the guesswork out of it.
Melatonin doesn’t act like a sleeping pill that “knocks you out”. Instead, it helps your body prepare for sleep. Its effects usually begin around 20-40 minutes after taking it, helping you fall asleep more easily by calming your body and signalling that it’s time to rest.
Most people find that melatonin supports a full night’s sleep of around 7 to 8 hours, though the duration can vary depending on dosage, timing, and your body’s natural rhythm. Because it helps regulate rather than induce sleep, melatonin is best used to restore balance to your sleep–wake cycle rather than as a nightly quick fix.
Timing is key when it comes to melatonin. It’s usually most effective when taken 20-40 minutes before bed, giving your body time to respond as natural melatonin levels rise. If you’re using it to manage jet lag or adjust to shift work, the timing might differ slightly. Your GP can advise on the best schedule to help reset your internal body clock.
Melatonin isn’t routinely recommended for children, and it should only ever be used under medical supervision. In some cases, doctors may prescribe it for children who have specific sleep disorders or conditions that affect their sleep patterns. However, for most children, building healthy sleep habits, like consistent bedtimes, calming bedtime routines, and reduced screen time before bed, is a safer and more effective way to improve sleep. If your child regularly struggles to fall asleep, it’s best to speak to a GP or paediatric sleep specialist before considering melatonin.
Beyond its well-known connection to sleep, melatonin has several other fascinating roles. It helps the body adapt to seasonal changes – influencing rhythms such as mood, metabolism, and temperature regulation – and even plays a part in certain animal and plant processes, from hibernation to protection against oxidative stress. In humans, melatonin acts as a powerful antioxidant, defending cells against damage from free radicals and supporting immune health. Research also links declining melatonin levels with ageing, suggesting its antioxidant and immune-modulating properties may help protect against some age-related diseases. It has also been found to reduce anxiety in patients prior to surgery, highlighting its ability to calm the mind and body. While its broader health benefits are still being explored, there’s no doubt that melatonin is more than just a sleep hormone.
Melatonin isn’t technically banned in the UK, but it is classed as a prescription-only medicine, meaning you can’t legally buy it over the counter as you can in some other countries. This regulation exists because melatonin is a hormone that affects your body’s internal clock, and its long-term effects aren’t fully understood. By keeping it prescription-only, UK health authorities ensure it’s used safely and appropriately, usually for short-term treatment of sleep problems, under a doctor’s guidance. In contrast, countries like the US allow melatonin to be sold as a supplement, but this also means it isn’t as tightly regulated. So, while you can’t pick it up freely in UK shops, this restriction helps protect people from potential misuse and ensures the right dose and timing are prescribed for each individual.
Melatonin is generally considered safe, with fewer side effects than other sleeping medicines. If you experience any melatonin side effects, such as adverse reactions or changes to how you normally feel, contact your doctor as soon as possible.
It’s also important to note that melatonin can cause issues if you’re taking other medicines, such as birth control and diabetes drugs.
Melatonin helps keep your body in tune with the natural rhythm of day and night, preparing you to rest and recharge. While supplements can be useful for short-term issues like jet lag, the best way to support healthy levels is through good habits like getting natural daylight, limiting screens before bed, and keeping a consistent sleep routine. Think of melatonin as your body’s gentle cue to unwind; by supporting it naturally, you’ll set yourself up for deeper, more restorative sleep.
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