For sports performance

The optimal dose for sports performance benefits is 3–6 mg per kilogram of bodyweight (approximately 200–400 mg in a 70 kg person), taken around 60 minutes before exercise.^[1] Using a dose at the low end of this range, approximately 3 mg/kg of caffeine before exercise (approximately 200 mg in a 70 kg person), achieves the benefits along with the lowest risk of side effects.^[2]

Safety in adults

Caffeine is generally safe for most people if used within the recommended amounts.^[3][4] The US Food and Drug Administration (FDA) and the European Food Safety Authority (EFSA) report that a daily total caffeine intake of up to 400 milligrams (mg) does not raise safety concerns for non-pregnant adults.^[5][6] The EFSA further reports that a daily total caffeine intake of up to 200 mg in pregnant and lactating women does not increase safety concerns for unborn babies or breastfed infants, and that a single caffeine dose of up to 200 mg (approximately 3 mg per kg bodyweight for a 70-kg adult) does not raise safety concerns.^[5] In other words, caffeine intake is unlikely to cause detrimental health effects if daily intake is below 400 mg/day in non-pregnant adults, or below 200 mg/day in pregnant/lactating women, and if a single dose is less than 200 mg.

Safety in children and teens

In children and adolescents, more research is needed to clarify safety, health risks, and tolerable upper intake limits.^[5] Evidence from a systematic review suggests that children and adolescents should consume no more than 2.5 mg per kg of bodyweight per day (equivalent to 100 mg for a 40 kg person).^[3] But some organizations discourage all consumption of caffeine and other stimulants by children and adolescents.^[6]

Caffeine in food and drink

Caffeine concentrations in various foods — coffee, tea, soft drinks (cola), chocolate, energy drinks, etc — are highly variable.^[5] For example, a cup of coffee may contain approximately 50–200 mg of caffeine, but the amount per cup is highly variable depending on the type of bean, how it is roasted, and how it is prepared.^[7][8] Some energy drinks contain very high amounts of caffeine, and the FDA recommends avoiding dietary supplements that contain pure or highly concentrated caffeine because a single teaspoon of pure powdered caffeine contains about 5 grams (5000 milligrams), far higher than the upper recommended limit of daily intake and approaching the toxic dose.^[9]

For a detailed overview of caffeine dosing, read our article “How Much Caffeine Is Too Much?”.

Caffeine in caffeine citrate

Note that caffeine citrate is about 50% caffeine by weight, i.e., a 50 mg dose of caffeine citrate contains approximately 25 mg of caffeine.^[10][11]