Substances and sleep
Coffee, alcohol, tobacco: how they affect the night.
What you drink or take during the day shows up at night. Here's how a few common substances act on sleep.
Coffee and stimulants
- Caffeine is a stimulant, and its effects last several hours. A coffee too late can delay falling asleep.
- Tea, cola and energy drinks also contain caffeine. Better to avoid them late in the day.
Alcohol
- Alcohol sometimes helps you doze off, but it fragments the night. The second half of sleep turns unstable, with awakenings.
Tobacco and cannabis
- Nicotine is a stimulant. Tobacco makes falling asleep harder and sleep lighter.
- Cannabis also changes sleep and can weigh on how you feel the next day.
Frequently asked questions
Does coffee keep you from sleeping?
Caffeine is a stimulant whose effects last several hours, so a coffee taken too late can delay falling asleep. Tea, cola and energy drinks contain it too: best avoided late in the day.
Does alcohol help you sleep better?
It sometimes helps you fall asleep, but it fragments the night. The second half of sleep becomes more unstable, with awakenings, and sleep ends up lower in quality.
Does tobacco affect sleep?
Yes. Nicotine is a stimulant: tobacco makes falling asleep harder and sleep lighter. Cannabis also alters sleep and can weigh on how you feel the next day.
Sources
Thinking of talking to a doctor about it?
Keep a sleep diary for a few weeks before the appointment: it makes the conversation easier and more useful.
Also worth reading
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