Drinking just one cup of coffee a day is linked to a reduced risk of the most common form of primary liver cancer according to -- and that includes both caffeinated and decaffeinated coffee.
The study by the University of Southampton along with researchers from the University of Edinburgh analyzed data from 26 observational studies involving more than 2.25 million participants.
The team set out to look at the effect of drinking between one and five cups of caffeinated coffee a day on hepatocellular cancer (HCC), the second leading cause of death from cancer globally, due to its poor prognosis and high frequency, especially in China and Southeast Asia.
The findings showed that drinking just one cup of coffee a day was associated with a 20 per cent reduction in the risk of developing HCC, two cups was associated with a 35 per cent reduction, and up to five cups with a 50 per cent reduction.
There was little data available above five cups a day to show what effect increasing consumption further may have.
Lead author Dr. Oliver Kennedy noted that "We're not suggesting that everyone should start drinking five cups of coffee a day though. There needs to be more investigation into the potential harms of high coffee-caffeine intake, and there is evidence it should be avoided in certain groups such as pregnant women."
The team also found that both existing coffee drinkers and new coffee drinkers benefited from the same reduced risk, and that decaffeinated coffee was also found to have a protective, although smaller, effect -- news which may encourage those who are not coffee lovers to make the drink a bigger part of their lifestyle.
Professor Peter Hayes of the University of Edinburgh, said, "We have shown that coffee reduces cirrhosis and also liver cancer in a dose-dependent manner. Coffee has also been reported to reduce the risk of death from many other causes. Our research adds to the evidence that, in moderation, coffee can be a wonderful natural medicine."
Kennedy also added, "Our findings are an important development given the increasing evidence of HCC globally and its poor prognosis."
It is estimated that by 2030, the number of new cases of HCC annually will have risen by about 50 per cent, to more than 1.2 million.
Increased coffee consumption has already been shown to protect against serious non-cancer chronic liver disease (cirrhosis), possibly due to the compound molecules in coffee possessing antioxidant, anti-inflammatory, anticarcinogenic, and other beneficial properties.
The study's findings were published in the journal BMJ Open.
