melatonin

Everyday

1. A natural chemical (a hormone) your body makes when it gets dark, which helps you feel sleepy. tree →
2. The same substance made in tablets or gummies, sometimes given by a doctor to help people sleep. tree →

In the lessons

In science and health lessons melatonin explains the body clock: darkness tells the brain to make melatonin, and bright light, especially screens at night, can stop it. That is why the lesson says to put phones away before bed. It also helps travellers with jet lag. Phrases: melatonin levels, take melatonin, melatonin and sleep.

Examples

• Your body makes melatonin when the room gets dark. tree →
• Bright screens at bedtime can lower your melatonin. tree →
• Melatonin helps you feel sleepy at night. tree →
• The doctor said my brother could take a small dose of melatonin. tree →
• Jet lag happens partly because your melatonin is on the wrong time. tree →
• Animals make melatonin too, which helps them know the seasons. tree →

Note

Uncountable: "melatonin is", not "a melatonin". Pronounced mel-a-TOH-nin. Not the same as melanin (the colouring in skin and hair). In some countries melatonin tablets need a prescription; children should only take them if a doctor says so. Myth: it is not a sleeping pill that knocks you out; it gently tells the body it is night.