Caffeine

Caffeine’s effect on exercise performance is among the best replicated in sports nutrition: trials and meta-analyses find small but consistent gains in endurance and repeated high-intensity efforts, typically at 3–6 mg per kg of body weight taken about an hour beforehand. It also reliably shortens and lightens sleep when taken later in the day, and individual responses vary widely. Health authorities generally regard up to about 400 mg a day as safe for most healthy adults, with lower limits in pregnancy.

Reviewed 2026-09-21

Official sources

Reviewed ingredient

This topic is also a reviewed ingredient, with dose context and claim-level evidence.

How this list was built

We searched Europe PMC for English-language papers published since 2015 whose title contains “caffeine” but not “preterm” or “prematurity” or “neonat” or “infant” or “paracetamol” or “acetaminophen” or “post-dural” or “postdural”, kept meta-analyses, systematic reviews and randomised trials, then ranked them by study design first, then recency and citations. Retracted papers are removed.

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