Caffeine-lovers rejoice, your morning latte might add a few more years to your life.
A new study of half a million British people found that those that drank a cup a day or more had a lower risk of dying early.
The study, published in the Journal of the American Medical Association, found people who drank one cup a day had a 6% lower risk of dying early, while those who drank six cups had a 16% lower risk.
The studies authors say that this makes coffee part of a healthy diet.
UK Biobank is a Britain-based study that follows the health and well-being of 500,000 volunteer participants and provides the data to approved researchers from academia and industry in the UK and overseas.
The researchers, from various institutions, including the National Cancer Institute and the National Institutes of Health, studied information on how much coffee people drank, how often and what type (including decaffeinated), their alcohol consumption, education and physical activity and whether they smoked.
After taking into account factors that would be harmful to health - such as smoking and alcohol - they found that fewer coffee drinkers died early than non-coffee drinkers. They were also less likely to die from heart disease and cancer, as well as other diseases.
In addition, it didn’t matter which type of coffee they drank: instant or ground, natural or decaffeinated.
Other studies agree
Another study last year reached similar conclusions.
When the International Agency for Research on Cancer and Imperial College London studied almost half a million people from 10 European countries, they found that higher levels of coffee consumption were associated with a reduced risk of death from all causes, particularly from circulatory diseases and diseases of the gut.
Coffee has also been shown to have a role in protecting against liver cancer, but only the caffeinated variety, according to a study led by the University of Southampton.
Drinking one cup more of caffeinated coffee a day was associated with a 20% reduction in the risk of developing the cancer, two cups more with a 35% reduction, and up to five cups with a halving of the risk.
Magic in a cup?
What is is about coffee that does this?
Researchers point to coffee having a host of beneficial ingredients. The roasted bean is a complex mixture of over 1,000 bioactive compounds, some with potentially therapeutic antioxidant, anti-inflammatory or anti-cancer effects.
Last year, an umbrella study which looked at more than 200 existing studies on the effects of coffee concluded that the largest benefit came from drinking three to four cups a day.
However, it also concluded that it could be harmful in pregnancy. High consumption was linked to low birth weight and premature birth.
There was also an association between women drinking coffee and a higher likelihood of suffering a bone fracture.
Last year, a United States court ruled that coffee companies in California must carry cancer warning labels, because the grounds contain a potentially toxic compound called acrylamide, which is produced during the roasting process.
None of the studies can prove that coffee is the reason for a lower risk of dying early, but they do show a link.
The authors of the umbrella study concluded that coffee was “generally safe” within “usual levels” of intake, and that “robust randomised controlled trials are needed to understand whether the observed associations are causal.”
Coffee drinking around the world
Northern Europeans are the most dependent on their morning caffeine, according to Euromonitor. The Finns consume the most coffee in the world, followed by the Swedes and Dutch. Brazil is the fifth biggest consumer of coffee, as well as the country that exports the most.