According to the European Food Safety Authority the following amounts of caffeine are considered safe to consume:
Adults
- Single doses of caffeine up to 200mg – about 3mg/kg body weight from all sources. The same amount of caffeine does not raise safety concerns when consumed less than two hours prior to intense physical exercise under normal environmental conditions. No studies are available in pregnant women or middle aged/elderly subjects undertaking intense physical exercise.
- Single doses of 100mg (about 1.4mg/kg body weight) of caffeine may affect sleep duration and patterns in some adults, particularly when consumed close to bedtime.
- Total intake up to 400mg per day (about 5.7mg/kg body weight per day) consumed throughout the day, but not for pregnant women.
Pregnant/lactating women
- Caffeine intake from all sources up to 200mg per day consumed throughout the day
Children and adolescents
- The single dose of caffeine considered to be of no concern for adults (3mg/kg body weight per day) may also be applied to children, because the rate at which children and adolescents process caffeine is at least that of adults, and the studies available on the acute effects of caffeine on anxiety and behaviour in children and adolescents support this level.
- A level of 3mg/kg body weight per day is also proposed for habitual caffeine consumption by children and adolescents.
Average caffeine content in drinks (according to the European Food Safety Authority)
Cup of filter coffee (200ml) 90 mg
Standard can of “energy drink” (250ml) 80 mg
Espresso (60ml) 80 mg
Cup of black tea (220ml) 50 mg
Standard can of cola (355ml) 40 mg
Bar of plain chocolate (50g) 25 mg
Bar of milk chocolate (50g) 10 mg