COFFEES at the biggest chains can contain as much caffeine as five cans of Red Bull, a Sun investigation reveals.
Starbucks, Costa and Caffe Nero are selling drinks with more caffeine per cup than adults should have at once.
Some contain almost the entire recommended daily limit.
Adults should have no more than 400mg of caffeine over the course of a day and no more than 200mg at any one time, experts say. But just one large Starbucks venti filter coffee would take people nearly up to the total daily limit.
It has 387mg of caffeine — the same as 12 cans of Coca Cola or nearly five cans of Red Bull.
At Costa, a large “massimo” americano or cappuccino contains 370mg. And regular-sized coffees at both Starbucks and Costa can contain more than the 200mg recommended maximum.
Caffe Nero’s largest “grande” americano has three shots of espresso, which is around 240mg of caffeine.
Too much can cause problems like anxiety, sleep problems and heart palpitations.
In extreme cases, people have died from caffeine overdoses.
Starbucks is the only major chain to publish the caffeine content of its drinks online.
Details of Costa and Caffe Nero drinks were published by the website Caffeine Informer.
Sun nutritionist Amanda Ursell said: “We have a right to know how much is in each coffee.”
A Starbucks spokesman said it published the information to “help customers make informed decisions”. Caffe Nero said customers could request fewer shots of espresso in their coffee. Costa refused to comment.