Melatonin, the sleep hormone: how light and routine affect its production

Melatonin is a hormone the brain produces in response to darkness. It helps set your internal clock and tells your body the day is over (NCCIH). Light in the evening, especially bright light, can block its production — so how you spend the last hours before bed has a noticeable effect on falling asleep.

The good news: your body does most of the work itself. Your job is not to get in its way and to give it clear signals: light during the day, dark in the evening.

Melatonin, the sleep hormone: how does it work?

Melatonin doesn't "switch you off" like a sleeping pill. It works as a time signal: levels rise when it gets dark and fall when it gets light (Mayo Clinic).

This signal helps coordinate your daily rhythm — sleep and wakefulness, body temperature, appetite. When your rhythm matches the actual day, it's easier to fall asleep and easier to wake up in the morning. More about your internal clock in our article on morning light and circadian rhythms.

With age, the body's own melatonin production naturally declines (Mayo Clinic). That's one reason routine and light become more and more important.

Melatonin and evening light: why do screens get in the way?

In short: light at night suppresses melatonin production, and blue light does so most of all. According to Harvard researchers, blue light suppressed melatonin for about twice as long as green light (Harvard Health).

Blue light comes from phone, laptop and TV screens, as well as many LED bulbs. Even fairly dim lighting in the evening can affect production of the hormone. More on this in our article "Blue light and sleep".

What you can do starting today:

• Put away bright screens two to three hours before bed, as Harvard Health advises (Harvard Health).
• In the evening, switch to warm, dim light: a floor lamp, a desk lamp, a night-light.
• For a night-light, choose a dim reddish light — it shifts your internal clock less.
• Make your bedroom dark: blackout curtains or a sleep mask.

How to increase melatonin naturally?

The key is contrast: lots of light during the day and little in the evening. According to Harvard Health, exposure to bright light during the day helps you sleep better at night (Harvard Health).

• Go outside in the morning, even briefly — even on a cloudy day it's much brighter outdoors than indoors.
• Work and eat breakfast by a window.
• Get up at the same time every day, including weekends: a consistent wake-up time sets the rhythm for the whole day.
• Plan late dinners and workouts so you still have time to wind down before bed.
• Create a short, repeatable evening ritual — you'll find ideas in our article on evening rituals for sound sleep.

If you're used to going to bed very late, shift your bedtime gradually — there's a step-by-step plan in "How to fix your sleep schedule". And when flying across time zones, tips on how to deal with jet lag will come in handy.

Melatonin supplements: what should you know?

Melatonin supplements are sold in many countries, but they aren't a harmless "vitamin." Before taking them, check with a doctor or pharmacist.

Things to keep in mind:

• Safety during pregnancy and breastfeeding hasn't been studied enough (NCCIH).
• Melatonin can interact with various medications — for example, drugs that affect blood clotting, blood pressure and blood sugar (Mayo Clinic).
• Side effects are possible: headache, dizziness, nausea, daytime sleepiness (Mayo Clinic).
• Supplements should be stored out of children's reach (NCCIH).

A supplement doesn't replace a routine: if you're surrounded by bright light in the evening with a screen in your hand, the "time to sleep" signal will still be blurred.

How to support evening relaxation without melatonin?

Once light and routine are in order, what's left is helping yourself relax. Some people choose breathing exercises, a warm shower or a book. Some add LifeWave products to their evening ritual.

According to the company, the Silent Nights patch helps you relax in the evening and contains no drugs, melatonin or sleeping pills: it responds to body heat and reflects specific wavelengths of light. Cellergize Evening drink is an evening dietary supplement with L-theanine, taurine and magnesium, also free of melatonin and sedatives; the company positions it as support for natural relaxation. If you're pregnant, breastfeeding, taking medication or have a health condition, talk to your doctor before taking the supplement.

But the foundation is still laid by simple things: light in the morning, darkness in the evening and a consistent wake-up time.