Caffeine
Stimulant
Reviewed human evidence related to caffeine. Effects depend on dose and context.
Last reviewed: 2026-09-16
Aliases: coffee caffeine
Reviewed outcomes
Endurance performance
Caffeine · increase · Magnitude unknown
Caffeine may improve endurance or prolonged intermittent sport performance.
strong evidence · Human data reviewedEvidence, caveats & sources›Sleep disruption
Caffeine · increase · Magnitude unknown
Caffeine can disturb sleep, especially with higher or later intake.
moderate evidence · Human data reviewedEvidence, caveats & sources›