How Much Coffee Is Ok for Me To Drink in a Day? I Asked the Experts
People have a love-hate relationship with coffee.
A 2023 report from the National Coffee Association found that 63% of Americans drink coffee every day – that’s more than any other beverage, except water. That same year, coffee reportedly overtook tea as the UK’s favorite drink; according to the British Coffee Association, the UK consumes about 98m cups of coffee a day.
On the other hand, many people seem to feel uneasy with how much brew they consume. An abundance of articles detail people’s quests to quit their coffee habits. And companies like MUD\WTR – which makes mushroom-based beverages – have advertised themselves as “healthier” alternatives to the regular cup of joe.
“Coffee has a bit of a bad boy reputation,” says Dr Peter Hayes, professor of hepatology at the University of Edinburgh. Current concerns about coffee, he notes, often reference the nebulous concept of “detoxing”, which is difficult to measure.
“Everybody talks in very vague terms,” he says, adding that coffee is not a toxin.
What is one to make of this? How much coffee is too much? Should we be trying to cut back?
We asked experts to break down the effects of our morning brew.
What happens when we drink coffee?
The main active ingredient in coffee is caffeine, explains Dr Sander Kersten, a professor of molecular nutrition at Cornell University.
Anyone who has guzzled a morning mug will be familiar with the effects. As a stimulant, caffeine makes one feel more alert, Kersten says. People’s reaction times are quicker, they are better able to concentrate, and they have increased endurance. Studies have found that caffeine consumption is linked to improved athletic performance.
According to Karsten, these effects usually kick in within half an hour and last up to two hours. “That’s probably the reason people tend to keep drinking coffee over the day,” he says. “It doesn’t last a long time.”
What are the health benefits of drinking coffee?
Experts agree that there are myriad benefits to our morning java. Coffee contains “hundreds if not thousands of components”, says Dr Edward Giovannucci, professor of nutrition and epidemiology at Harvard University’s TH Chan School of Public Health.
Some of these components “may have a range of beneficial effects, which might improve health over the long run”, he notes.
Certain compounds, for example, have strong anti-inflammatory and antioxidant properties, Giovannucci explains. Others reduce insulin resistance, which is a risk factor for diabetes.
In a meta-analysis of the effects of coffee consumption on health, Hayes and his colleagues found that drinking three to four cups a day was associated with lower risks of cardiovascular mortality, certain cancers and neurological, metabolic and liver conditions.
The liver in particular seems to thrive on coffee. One cup of coffee a day can reduce the risk of cirrhosis by 20%, and five cups a day can reduce the risk by 80%, Hayes says.
Hayes also notes that “it’s important to differentiate coffee from caffeine”. For example, a drinker can see these benefits even with decaffeinated coffee. “So there’s something in the coffee, and it’s not the caffeine, that is protective to the liver,” he says. “Apart from the liver, the more the better is not true.”
