Melatonin: what it does, and what it doesn't

Melatonin is a hormone your body produces naturally in response to darkness. Supplements are mainly useful for shifting your body clock, not as a general sedative.

When it helps most

• Jet lag and time zone changes.
• Shift work sleep adjustment.
• Delayed sleep phase (very late natural bedtime).

Precautions

Low doses (0.5-3mg) taken a few hours before target bedtime are generally more effective than high doses taken right before bed. Melatonin can interact with medications — check with a doctor or pharmacist first, especially for children, pregnant people, or those on other medication.