It's blamed for sleeplessness, anxiety, frequent toilet trips and worse - but caffeine is harmless, a new study shows.
The stimulant, long ridiculed by those who believe it to be harmful, is safe - even for pregnant women and young children.
A review of 44 trials dispelled the widespread myth that caffeine, found in tea, coffee and fizzy drinks, is bad for the body.
It found that sticking to the recommended daily amount of 400mg - the equivalent four cups of coffee or eight cups of tea - has no lasting damage on the body.
Conducted by a leading British dietitian, the paper also shows the substance boosts both mental and physical performance.