Drinking coffee is good for most people’s health, a major review of medical evidence has concluded.
The drink is more likely to ward off disease than to cause harm, according to the most comprehensive report yet conducted.
Three to four cups a day confers the greatest benefit, the University of Southampton researchers found, cutting the risk of heart disease by 15 per cent and the chance of an early death by 17 per cent.
They also found evidence it reduces the chance of certain cancers, diabetes, liver disease and dementia.
The scientists, whose report was published last night in the British Medical Journal, found drinking coffee in moderation is ‘more likely to benefit health than harm’.
Three to four cups a day cuts the risk of heart disease by 15 per cent and an early death by 17 per cent (stock image)
But they stressed their findings do not mean it is good for everyone.
Pregnant women, for example, are at greater risk of losing their baby if they drink too much coffee, and the caffeine also slightly raises the risk of bone fractures among women.
But overall they found people who drink coffee are more likely to benefit than not.
They wrote: ‘Coffee is highly consumed worldwide and could have positive health benefits, especially in chronic liver disease.
‘Coffee consumption seems generally safe within usual levels of intake, with summary estimates indicating largest risk reduction for various health outcomes at three to four cups a day, and more likely to benefit health than harm.’
Antioxidants are responsible
The scientists believe the antioxidant plant compounds in coffee are responsible for the benefits.
Decaffeinated coffee has a similar impact to the standard version, they found, suggesting the caffeine is not responsible for health benefits.
‘Roasted coffee is a complex mixture of over 1,000 bioactive compounds, some with potentially therapeutic antioxidant, anti-inflammatory, antifibrotic, or anticancer effects,’ they wrote.
The research team, which also included experts from the University of Edinburgh, reviewed all the available evidence on coffee consumption, combining the findings of 201 published studies.
They found it had a major impact on heart problems, cutting the risk of developing cardiovascular disease by 15 per cent and slashing the chance of a cardiovascular death by 19 per cent.
It also cuts the risk of liver cancer by 34 per cent and bowel cancer by 17 per cent – but actually seems to increase the risk of leukaemia, lymphoma and lung cancer.
Coffee drinkers have a 36 per cent lower chance of developing Parkinson’s disease and a 27 per cent lower risk of Alzheimer’s, they found.
More cups does not bring extra benefits
HOW MUCH CAFFEINE IS SAFE?
The EU’s food safety watchdog advised a daily limit of 400mg for adults in its first guidelines on caffeine intake in 2015.
European Food Safety Agency officials suggested pregnant women should keep intakes below 200mg.
It also advised children to consume no more than 3mg of caffeine per KG of body weight – the equivalent of two mugs of milky tea for a child of four.
Health officials warned those who break the limits run the risk of a host of health problems, from anxiety to heart failure.
Its warning also showed links between high caffeine intake in pregnancy and having a baby that is underweight.
The NHS says too much caffeine can cause a miscarriage. There are also links to birth defects.
However, with coffee far from the only food or drink to contain caffeine, people may unintentionally be going over the safe limit.
The researchers found people who drank more than three cups a day did not tend to see any additional benefits, and other studies have shown people who drink much more than this start to do themselves harm.
The European Food Safety Agency advises that people drink no more than four cups a day.
It says those who drink more than this each day run the risk anxiety, sleeplessness, heart rhythm disturbances or heart failure.
In an editorial also published in the BMJ, Eliseo Guallar of the Johns Hopkins Bloomberg School of Public Health said people should not start drinking coffee for health reasons.
While overall it may be beneficial, some people may be at higher risk of adverse effects, he said, and there is ‘substantial uncertainty’ about the effects of higher levels of intake.
Coffee is often drunk sugar and milk or cream, he said, which ‘may independently contribute to adverse health outcomes’.
Coffee is one of the world’s most commonly consumed drinks, with an estimated 2.25billion cups drank around the world each day.
Its use is thought to date back to 11th-century Ethiopia, where legend says a goat herder noticed his animals became energetic after eating the berries from a coffee tree.
Until recently people were warned against drinking more than a few cups of coffee a day, for fear that it might cause cancer.
But last year the World Health Organisation withdrew its previous warnings on the link between coffee and bladder cancer – and instead said that the drink could, in fact, help protect against certain cancers such as womb cancer and liver cancer.
Pregnant women are advised by the NHS to drink no more than two cups a day.