How much caffeine is too much?
Last updated September 3, 2026.
The FDA puts the healthy-adult ceiling at 400 mg a day - about four cups of coffee - with 200 mg in pregnancy. Jitters, poor sleep, and a racing heart mean your personal limit is lower.
What to do
- Count everything - coffee, tea, energy drinks, soda, pre-workout, chocolate.
- Respect the half-life - caffeine lingers 4-6 hours, so set an afternoon cutoff.
- Cap at 200 mg in pregnancy - and keep caffeine away from kids.
- Never touch pure caffeine powder - the FDA warns one teaspoon equals ~28 cups of coffee.
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