Researchers at Kaiser Permanente Medical Care Program, Oakland, California studied 125,580 people and found that for each cup of coffee they drank per day, participants were 22 percent less likely to develop alcoholic cirrhosis.
Long-term heavy drinking is the most common cause of cirrhosis, but many other factors play a role in whether or not a chronic drinker develops the liver disease, such as genetics, diet and nutrition, smoking and the interaction of alcohol with other toxins, the authors said.
Participants were surveyed about how much alcohol, coffee and tea they drank per day during the past year. Some had their blood tested for levels of certain liver enzymes which are detected when the liver is diseased or damaged.
Lower Risk of Cirrhosis
For each cup of coffee they drank per day, participants were 22 percent less likely to develop alcoholic cirrhosis. Drinking coffee was also associated with a slight reduction in risk for other types of cirrhosis, other than alcoholic cirrhosis.
Participants who drank both alcohol and coffee had lower liver enzyme levels than those who only drank alcohol.
The difference in liver enzyme levels was greatest for those who were the heaviest alcohol drinkers.
Tea drinking was not related to reduced risk, suggesting that it is not caffeine that is responsible for the relationship between coffee and reduced cirrhosis risk.
The study had not resolved the issue of ingredient or property in coffee offers protection against developing liver disease. Previous reports are disparate with respect to whether the apparently protective coffee ingredient is caffeine; in our opinion this issue is quite unresolved.
Even if coffee is protective, the primary approach to reduction of alcoholic cirrhosis is avoidance or cessation of heavy alcohol drinking, assuming causality, the data do suggest that coffee intake may partly explain the variability of cirrhosis risk in alcohol consumers. Basic research about hepatic coffee-ethanol interactions is warranted, but we should keep in mind that coffee might represent only one of a number of potential cirrhosis risk modulators.