Drinking coffee could be having unexpected health benefits and even increasing our lifespan by up to nine minutes a day, new research suggests.
Two new studies, including the largest ever conducted into coffee drinking, have found that imbibing even a single cup a day reduces the risk of dying early from any cause, and dramatically cuts the chance of death from digestive problems.
People who consumed just one 350ml cup each day slashed their risk of dying early by 12 per cent over 16 years, while three cups reduced the risk by 18 per cent.
Prof Sir David Spiegelhalter, Winton Professor for the Public Understanding of Risk at the University of Cambridge, calculated that, if causal, it meant a cup of coffee a day extended the average life of a man by three months and a woman by a month.
“Pro-rata, that’s as if that cup of coffee puts, on average, around nine minutes on a man’s life, and around three minutes on a woman’s. So perhaps we should relax and enjoy it,” he said.Researchers from Imperial College London and the University of Southern California (USC) who conducted the studies say the protective effect of coffee is biologically plausible because the drink contains antioxidants and health boosting compounds which combat insulin resistance, lower inflammation and improve liver function.
“If you like to drink coffee, drink up. If you’re not a coffee drinker, then you need to consider if you should start,” said Dr Veronica Setiawan, associate professor of preventative medicine at USC.
“Coffee contains a lot of antioxidants and phenolic compounds that play an important role in cancer prevention.
“Although this study does not show causation or point to what chemicals in coffee may have this ‘elixir effect,’ it is clear that coffee can be incorporated into a healthy diet and lifestyle.”
Coffee is one of the world’s most commonly consumed beverages, and Britons now drink 55 million cups a day according to the British Coffee Association. One in eight people in the UK now visits a coffee shop on a daily basis.
For the Imperial study researchers analysed data from more than half a million people aged 35 or over from 10 EU countries, including Britain, France, Denmark and Italy.
After 16 years of follow up, almost 42,000 people in the study had died from a range of conditions including cancer, circulatory diseases, heart failure and stroke.
After taking into account lifestyle factors such as diet and smoking, the researchers found that the group with the highest consumption of coffee had a lower risk for all-causes of death, compared to those who did not drink coffee.
Men who drank at least two and a half cups a day reduced their risk by 12 per cent and women by 7 per cent.
It also reduced the risk of dying from digestive diseases by 51 per cent for men, and 40 per cent for women, and lowered the risk of death from circulatory disease for women by 22 per cent.
In a sub-set of 14,000 people, the team also analysed metabolic biomarkers, and found that coffee drinkers have healthier livers overall and better glucose control than non-coffee drinkers.
“We found that higher coffee consumption was associated with a lower risk of death from any cause, and specifically for circulatory diseases, and digestive diseases,” said lead author Dr Marc Gunter of the International Agency for Research on Cancer (IARC) and formerly at Imperial’s School of Public Health.
“We found that drinking more coffee was associated with a more favourable liver function profile and immune response.
“This, along with the consistency of the results with other studies in the US and Japan gives us greater confidence that coffee may have beneficial health effects.
“Our results suggest that moderate coffee drinking – up to around three cups per day – is not detrimental to your health, and that incorporating coffee into your diet could have health benefits.”
A separate study of 215,000 people by USC found even one cup of coffee a day reduced death by 12 per cent for both men and women and three cups reduced risk of dying early by 18 per cent.
Previous research by USC and others have indicated that drinking coffee is associated with reduced risk of several types of cancer, diabetes, liver disease, Parkinson’s disease, Type 2 diabetes and other chronic diseases.
The researchers are now hoping to study coffee in detail to understand which compounds are driving the beneficial health effects and are even considering whether coffee drinking could become an important public health intervention.
Professor Elio Riboli, head of the School of Public Health at Imperial, said: “These findings add to a growing body of evidence which indicates that drinking coffee not only is safe, but it may actually have a protective health effect for people.
“While further research is needed, we can be confident that the results from a large European study confirm previous findings seen around the world.”
Last year the World Health Organisation removed coffee as a carcinogen and said it could reduce the risk for liver and uterine cancer.
Prof Naveed Sattar, Professor of Metabolic Medicine, University of Glasgow, said:
“This is a very nice paper, written by an excellent group and very well done, but its conclusions will not lead me to start drinking coffee or to recommend people drink more coffee as a way to lessen their risks for heart disease.
“Why not? I remain unconvinced that the link between coffee and heart disease represents a true cause and effect relationship and that coffee is truly protective, regardless of how large a study suggests this.”
Both new studies were published in Annals of Internal Medicine.