Morning light: how to reset your body clock and sleep better

Morning light and circadian rhythm are the key pair for better sleep: bright light in the first hours after waking sets your internal clock, and falling asleep at night gets easier. Just 10–15 minutes outdoors is enough to set the rhythm for the whole day (Sleep Foundation).

Your brain has its own "clock" — a group of cells that sets the rhythm of sleep and wakefulness, body temperature, appetite and hormone production. This clock doesn't run at exactly 24 hours, so it needs resetting every day. Its main cue is light.

What is the circadian rhythm and how does it affect sleep?

The circadian rhythm is the daily cycle your body lives by. When it matches the actual day, you feel more alert in the morning and fall asleep more easily at night.

When the rhythm is off, you feel groggy in the morning, sleepy during the day and wide awake closer to night. That happens after late evenings in front of a screen, working indoors without windows, after a flight or when the clocks change.

Why does morning light exposure matter for your circadian rhythm?

Bright light in the first hours after waking tells your brain that the day has started. In the evening this helps you feel sleepy earlier and fall asleep more easily.

Even on a cloudy day there's many times more light outdoors than in a room with a lamp. That's why a short trip outside works better than the brightest lighting at home.

• Go outside within the first hour after getting up for at least 10–15 minutes.
• Combine it with a walk — that way you also get some light exercise (see "Benefits of walking").
• Have breakfast by a window, not in a dark kitchen.
• At the office, choose a spot near a window and step outside at lunchtime.

How does evening light keep you from falling asleep?

Bright cool light late in the evening signals "still daytime" to your clock and pushes sleep later. That's why it's worth dimming the lights in the evening.

• An hour or two before bed, switch to warm, dim lighting.
• Turn on night mode on your screens — or better, put your phone away (NHS).
• Keep your bedroom dark: blackout curtains or a sleep mask.

For more on how screens affect falling asleep, see "Blue light and sleep".

Who needs a light routine the most?

People who spend the day indoors, who often cross time zones, and older adults.

• Office workers who hardly get outside during the day.
• Travelers: for them light becomes the main tool for adjusting after jet lag.
• Older adults: sensitivity to light declines with age, and the daily rhythm gets "blurred".
• Anyone who's used to falling asleep late and wants to shift to an earlier schedule.

How to set your circadian rhythm with a morning routine

A good morning is light, water and a filling breakfast. Together they set the rhythm for the whole day. Wake up, open the curtains, drink a glass of water, go for a short walk, have breakfast by the window. Regularity matters more than duration here: ten minutes every day does more than an hour at the weekend.

In the evening light works the other way around: the softer it is, the easier it is to fall asleep. To build your whole sleep routine, read "How much sleep do adults need?".

What if it's dark in the morning?

In fall and winter many people get up before sunrise, and getting into daylight right away isn't possible. In that case, turn on bright overhead lights at home as soon as you wake up and go outside at the first opportunity — for example, walk part of the way to work or step out during your lunch break.

The weekend is no reason to break your rhythm completely. Try to get up at about the same time as on weekdays and go straight into the light: that way your internal clock won't shift every week. For tips on getting through the clock change, see "Daylight saving time and sleep".

You can round out your morning routine with the Cellergize Morning drink with vitamins, minerals and amino acids, or Energy Enhancer patches — they're caffeine-free. And for the evening, when the lights are low, LifeWave offers the Silent Nights patch, which, according to the company, helps you relax before bed.