Costa beats Starbucks in UK high-street caffeine levels test

A medium cappuccino at Costa contains 325mg of caffeine. Bloomberg

The high street battle for coffee loyalty is an intensely competitive world but there are stark differences in the levels of caffeine, according to research by consumer group Which?

Costa Signature Blend was the strongest cappuccino and Pret a Manger delivered the strongest espresso while Starbucks came out bottom for levels of caffeine in both the cappuccino and espresso tests.

Which? tested five chains — Costa, Pret, Starbucks, Caffe Nero and Greggs — and measured caffeine content in a medium cappuccino and an espresso. For Greggs, Pret and Starbucks they also tested filter coffee.

For comparison, a 250ml can of Red Bull contains 80mg of caffeine.

A medium cappuccino at Costa contains a “massive” 325mg of caffeine — around the amount contained in four cups of tea — almost five times the strength of a cappuccino from Starbucks, which contains the least at 66mg, Which? found.

Cappuccinos from Greggs and Pret also contain significantly less caffeine than Costa, as 197mg and 180mg respectively.

Caffe Nero had the second lowest levels of caffeine and was ranked fourth above Starbucks for both cappuccinos, at 110mg-115mg, and espresso at 45mg.

A single espresso from Pret contains 180mg of caffeine, six times as much as one from Starbucks which had a “meagre” 33mg, according to the watchdog's findings.

Pret’s filter coffee also contained the most caffeine at 271mg, two and a half times as much as the Starbucks version, which contained 102mg. Greggs was second to Pret for its caffeine levels in filter coffee with 225mg per cup.

“Many of us rely on coffee to get us through the dark winter mornings, but our research shows you may be consuming significantly more, or less, caffeine than you bargained for,” Which? nutritionist Shefalee Loth said.

“Our analysis has shown that there are big variations in caffeine content between drinks from different high-street coffee shops.

“Most of the time this shouldn't be an issue but if you drink a lot of coffee or need to limit your caffeine intake you might want to consider what you're ordering and where from.”

Variations are not only due to the number of caffeine shots used across the chains but also the type of coffee bean, of which there are two main types — Arabica and Robusta.

Arabica beans contain around half the caffeine of Robusta beans, and there are also variations in taste between the two.

However, the findings show buying coffee on the high street could be potentially problematic for consumers who are sensitive to caffeine, or are pregnant.

The National Health Service says pregnant women should consume no more than 200mg of caffeine per day, advising that a mug of instant coffee contains 100mg and a mug of filter coffee contains 140mg

A Costa Coffee spokeswoman said: “The amount of caffeine included within each coffee varies, depending on both the coffee and size of drink ordered by a customer.”

Pret declined to comment.