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What is melatonin?

Medicine & HealthLesson on requestFree to read

Quick answer

Melatonin is a hormone made by the brain's pineal gland that signals to your body that it is time to sleep. Its levels rise in darkness and fall with light, helping regulate your daily sleep-wake cycle. It is produced by the pineal gland in the brain, mainly at night.

Key things to understand

  1. It is produced by the pineal gland in the brain, mainly at night.
  2. Darkness triggers its release; light — especially blue light — suppresses it.
  3. It tells the body 'it's night', helping you feel sleepy — it doesn't knock you out like a sedative.
  4. It is made from serotonin, linking mood and sleep chemistry.
  5. Supplements are sometimes used for jet lag or shift-work sleep problems.

People also ask

Does melatonin make you fall asleep?
It signals that it is night and helps prepare the body for sleep, but it is not a sedative — it nudges your body clock rather than forcing sleep.
Why does screen light affect melatonin?
Blue-rich light at night tells the brain it is still daytime, suppressing melatonin and making it harder to fall asleep.
Is melatonin the same as a sleeping pill?
No. Sleeping pills sedate the brain; melatonin works with your natural body clock to signal night, which is gentler but less forceful.

Part of the guide: How Your Body Works →