Why the full moon can disturb your sleep

If you find yourself lying awake staring at a bright square of light on the ceiling every few weeks, you are in good company. Plenty of people report sleeping more lightly in the days around the full moon — dropping off later, waking more often and feeling less restored in the morning. The research on this is genuinely mixed, and it is wise to hold any single study lightly. What matters practically is that the effect feels real to you.

Part of it is simple physics. A full moon in a clear sky throws real light into a bedroom, and even a modest amount can nudge the body's sleep-wake signalling. Part of it is expectation: if you think you will sleep badly, you notice every wake-up and start worrying about the next one. And part of it is rhythm — the full moon is a monthly marker, arriving alongside whatever else is happening in your life. Rather than fighting any of this, it helps to work with it. A few small, repeatable adjustments will protect your rest whether the moon is full, new or somewhere in between.

Darken the room properly

Light is the strongest lever you have, and it is often the one people overlook. Thin curtains in a rented flat or a streetlamp outside the window can affect your sleep far more than the moon itself. Try these, in order of effort:

• Blackout curtains or a lining. Look for fabric that reaches the floor and overlaps the window frame at the sides. If you cannot fit a pole, a blackout blind held up with removable hooks works surprisingly well.
• An eye mask. Choose a soft, moulded shape that does not press on your eyes. Wear it for several nights in a row so it becomes a cue rather than a novelty.
• Deal with the small glows. Standby lights, a charger, a smoke alarm and a digital clock all add up. A strip of low-tack tape or a folded sock over a light is enough.
• Close the curtains before dusk in summer. British evenings stay light until late, so five minutes of tidying the room at teatime pays off at bedtime.

Cool the air and warm the body

Sleep tends to arrive more easily when your core temperature drops by a degree or so. A bedroom between roughly 16°C and 19°C suits most adults, so open a window earlier in the evening rather than at bedtime, and let the room air before you get in. In a heatwave, a bowl of ice in front of a fan, or a cotton sheet instead of a duvet, can make the difference between dozing and lying awake.

A warm bath or shower an hour or two before bed is one of the most reliable tricks there is. The warmth draws blood to the skin, and the cooling that follows helps sleep come. Keep your feet warm if they tend to run cold — bed socks are not unglamorous, they are practical. Choose bedding you can adjust easily, so you are not throwing off a heavy tog duvet at 3am.

Build a wind-down that starts well before bed

The hour before sleep matters more than the moment you climb in, especially on bright moonlit nights when your body may be more alert than usual.

• Dim the lights. Swap the overhead bulb for a lamp with a warm, low-wattage glow. Your brain reads dim, warm light as a signal that the day is closing.
• Step away from bright screens. If you must use a phone, turn the brightness right down and keep it brief. A paper book or a magazine is kinder.
• Choose a calming drink. Chamomile, lemon balm or warm milk with honey are all soothing. Be wary of alcohol as a sleep aid — it may help you drop off but fragments the second half of the night.
• Write it down. Three lines in a notebook: what is done, what can wait until tomorrow, what is worrying you. Emptying your head onto paper stops it circling.
• Keep the timing steady. A consistent bedtime and wake time, even at weekends, does more for sleep than any single remedy.

Turn the lunar cycle into a gentle check-in

Instead of treating the full moon as a threat, use it as a monthly prompt. For three months, note in a notebook how you slept in the two nights either side of it — how long it took to fall asleep, how often you woke, how you felt at breakfast. Most people discover a pattern, and a pattern you can see is far less unsettling than a vague sense of dread.

There is a seasonal rhythm here too. In winter, a full moon rides a long night, which makes it a good excuse for an early bath, an earlier bedtime and a lamp instead of the main light. In summer, when the moon rises late and the sky never quite darkens, cooling the room and closing the curtains early matters more. A short walk outside at dusk — ten or fifteen minutes, not a workout — is a lovely way to mark the shift from day to evening and helps set your body clock for the night ahead.

If you do wake in the night

Waking in the small hours is normal, and the annoyance is usually worse than the wakefulness. The trick is not to lie there for more than about twenty minutes. Get up, keep the lights low, and sit somewhere quiet with a book or a mug of something caffeine-free. Turn the clock away from the bed so you cannot check the time.

Slow breathing helps: in through the nose for four counts, out for six, for a few minutes, letting your shoulders drop. When you feel drowsy again, go back to bed. If poor sleep persists for weeks, or you snore heavily and wake unrefreshed, speak to your GP — there may be something more than moonlight at work.