Drinking around three cups of coffee a day has been linked to a lower risk of death “from any cause” in two new large-scale studies.
The habits of coffee-lovers were shown to add years to their life – with high coffee consumption shown to reduce the risk of death from diseases related to circulation and digestion in particular.
While scientists say more research is needed to prove coffee is definitely behind the effects observed in the studies, experts believe the antioxidant plant compounds found in the drink, rather than its caffeine, are responsible for its potentially life-extending effect.
Researchers from Imperial College London and the International Agency for Research on Cancer (IARC) analysed data on the health and coffee-drinking habits of more than half a million people from 10 European countries, including the UK.
They found men who drank at least three cups of coffee a day were 18 per cent less likely to die from any cause than non-coffee drinkers, with women experiencing an eight per cent reduction in mortality over the same period.
Meanwhile, American scientists conducted a separate investigation into the effect of coffee on the health of more than 185,000 participants from different ethnic backgrounds.
People who drank one cup of coffee daily were 12 per cent less likely to die than those who drank no coffee, irrespective of ethnicity, while drinking two to three cups of coffee appeared to reduce the chances of death by 18 per cent.
Experts praised the robust nature of the studies, but warned that further research was needed to prove that the effects observed were caused by the coffee itself, and not other factors.
The US study’s lead author, Dr Veronica Setiawan, from the University of Southern California, said the chemical make-up of the popular beverage was a possible explanation for the findings.
“Coffee contains a lot of antioxidants and phenolic compounds that play an important role in cancer prevention,” she said.
“We cannot say drinking coffee will prolong your life, but we see an association. If you like to drink coffee, drink up! If you’re not a coffee drinker, then you need to consider if you should start.”
Whether the coffee contained caffeine or was decaffeinated did not appear to make a difference in the two studies, both published in the journal Annals of Internal Medicine.
The studies were adjusted for a number of lifestyle factors, such as smoking and diet, to try and isolate and analyse the effects of coffee drinking on health and mortality rates.
Commenting on the research, statistics expert Professor Kevin McConway, from The Open University, said both papers were “well-conducted and large, and show similar results across several different populations and ethnic groups”.
“As a coffee drinker myself, they do reassure me that my habit probably isn’t bad for me,” he said. “However, if I didn’t already drink coffee, I’m not sure that they would persuade me to take it up for the good of my health.
“That’s because the size of the potential protective effect of coffee, in these studies, is not very large; because we can’t be sure what is causing what; and because, even if coffee drinking is somehow directly improving people’s health on average, neither study throws much light on exactly how it might do that.”