James Rowe: Not all coffee is made equal, as our research found.
Hello, I'm James Rowe and welcome to Which? Shorts, your free weekly insight into Which? Magazine, as well as our Money, Tech, Travel, and Gardening titles too.
Today I'm bringing you a piece that our chief nutritionist, Shefalee Loth, and senior health writer, Ayesha Muttucumaru, wrote for the October issue of Which? Magazine, all about high-street coffee shops.
You might think that the only difference between coffees bought in store is the taste and the flavour, but our research suggests otherwise. Here, Shefalee and Ayesha reveal that where you buy your coffee from could make a big difference to your daily caffeine intake, with some high-street coffees containing nearly four times as much caffeine as others.
Here's Shefalee and Ayesha's piece, adapted for the podcast, this week read by Shefalee herself.
Shefalee Loth: You might think a latte or espresso is pretty much the same drink wherever you buy it, but our research found wildly varying caffeine levels between Caffè Nero, Costa, Greggs, Pret, and Starbucks.
A medium Costa cappuccino at 332 ml packs over three and a half times as much caffeine as a similar-sized tall Starbucks – 325 mg of caffeine compared to 89 mg. The Costa choice has more caffeine than four 250 ml cans of Red Bull.
Meanwhile, a 50 ml single espresso from Pret contains nearly four times the caffeine and is twice the size of a Starbucks equivalent.
Interestingly, caffeine levels have changed since our last analysis in 2023. Some drinks have increased significantly, while others remain broadly similar.
Starbucks tells us that the reason why some values have changed in the last three years is because they've introduced improved testing protocols. These provide a more accurate measure of caffeine for individual drinks. So, if you're looking for a coffee from its menu that provides more of a boost, you might want to consider choosing their freshly brewed coffee over a frothy latte. Conversely, if you're looking to lessen your caffeine intake, choose a milky coffee instead.
Why does the caffeine content vary so much on the high street? The difference is partly down to how much coffee your drink actually contains and how many shots of espresso are used to make it. Other factors that can influence the caffeine content of seemingly identical drinks, and how it fluctuates over time, include the serving size, brewing method, water temperature, and the type of coffee beans used.
There are two main types of coffee bean: Arabica and Robusta. Robusta beans contain roughly double the caffeine of Arabica beans.
The coffee shops we've included in our comparison use one or the other, or a combination of both. While Pret and Starbucks use Arabica beans, Costa and Greggs use a mixture of both.
Where the beans originate from and their growing conditions – for example, the climate and soil – can also make a difference to their caffeine content.
If you're concerned, you can ask about the caffeine content or opt for fewer shots in your coffee. Alternatively, as Pret told us, you can also ask for a decaf version of most caffeinated drinks. A 355 ml decaf latte at Pret contains 6 mg of caffeine, while a decaf coffee at Costa contains 2 mg of caffeine.
What about matcha? Matcha is continuing to have its moment in the spotlight, and its popularity has surged over recent years. However, much like its coffee counterpart, caffeine content can also vary significantly between different matcha lattes due to the type and amount of matcha powder used.
The difference is stark: a medium matcha latte from Costa serves 99 mg of caffeine compared to 28 mg for a Pret version. This equates to three and a half times more caffeine in Costa's matcha latte compared to Pret's.
While we focused on hot matcha lattes for this comparison, we found that a tall iced matcha green tea latte from Starbucks had a similar caffeine level – 56 mg – to a tall hot matcha green tea latte – 57 mg. However, the most interesting finding was that Costa's matcha latte contains more caffeine than a Starbucks cappuccino, flat white, latte, and americano. So matcha could provide more of an energy boost than many of us think, depending on where you buy your latte from.
Are there any health benefits of coffee? The short answer is yes. Coffee has been associated with greater longevity, reduced inflammation, and improved liver health. These benefits are largely attributed to polyphenols, which are naturally found in coffee and other foods and act as antioxidants.
Coffee can also support gut health and a more diverse gut microbiome, possibly because it contains soluble fibre and compounds with prebiotic properties. This is based on research led by King's College London's Professor Tim Spector and colleagues at the ZOE gut study using data from more than 22,000 people and comparisons with microbiome data from 25 countries.
While there are health benefits to drinking coffee, too much caffeine can trigger anxiety, sleep disruption, and a rapid heart rate. Adults are advised to have no more than 400 mg a day. Pregnant and breastfeeding women should limit this intake to 200 mg.
As caffeine is also in tea, chocolate, colas, energy drinks, and some over-the-counter flu remedies, hitting that limit can happen faster than you think. But it's not always easy to see how much you consume. We had to sift through online documents and ask company press offices to get hold of all the data.
When you buy a beer, the alcohol-by-volume information is shown clearly. Shouldn't caffeine information be similar, or at least easily available on request?
If you're sensitive to caffeine or concerned you might be consuming too much, ask for one shot in your drink or switch to decaf.
James Rowe: That brings to an end another podcast from Which? There's loads more for you to read about everything we discussed today – just head to the episode description for more useful everyday advice.
There, you'll also find an exclusive offer for podcast listeners like you to become a Which? member for 50% off the usual price, giving you access to our product reviews, our app, one-to-one personalised buying advice, and every issue of Which? Magazine across the year. Plus, your membership helps us to make life simpler, fairer, and safer for everyone.
If you'd like to know when we release a new episode, then make sure you press subscribe wherever you're listening. That way, you can be one of the first to listen. And for any questions, comments, or anything in between, follow us on social media @WhichUK or email us, podcast@which.co.uk.
Goodbye.
