Drinking Coffee Could Help Protect Liver

13/06/06 Drinking coffee could help protect against alcohol-related cirrhosis of the liver. That's the finding of a new study in the June 12 issue of the Archives of Internal Medicine.

Researchers at Kaiser Permanente in Oakland, Calif., followed more than 125,000 health plan members who underwent a medical exam between 1978 and 1985. At the time, none of the members had diagnosed liver disease. Participants filled out a questionnaire detailing how much alcohol, coffee and tea they drank per day. By the end of 2001, 330 participants had been diagnosed with liver disease, including 199 with alcoholic cirrhosis. The researchers found that the more coffee a person drank, the less likely they were to develop alcoholic cirrhosis of the liver.

"Consuming coffee seems to have some protective benefits against alcoholic cirrhosis, and the more coffee a person consumes the less risk they seem to have of being hospitalized or dying of alcoholic cirrhosis," said Arthur Klatsky, MD, an investigator with Kaiser Permanente's Division of Research and the lead author of the study. "We did not see a similar protective association between coffee and non-alcoholic cirrhosis."

"This is not a recommendation to drink coffee," said Klatsky. "Nor is it a recommendation that the way to deal with heavy alcohol consumption is to drink more coffee. The value of this study is that it may offer us some clues as to the biochemical processes taking place inside liver cells that could help in finding new ways to protect the liver against injury."

The researchers found that people drinking one cup of coffee a day were, on average, 20 percent less likely to have alcoholic cirrhosis. For people drinking two or three cups the reduction was 40 percent, and for those drinking four or more cups of coffee a day the reduction in risk was 80 percent.

"Even allowing for statistical variation, this shows there is a clear association between coffee consumption, and protection against alcoholic cirrhosis," said Klatsky.

Cirrhosis is a disease that causes progressive damage, and impaired function of the liver. There are numerous causes, including alcohol, viruses, obesity or genetic problems. According to the National Center for Health Statistics, there are more than 5 million cases of chronic liver disease and cirrhosis in the United States, and nearly 28,000 people die of chronic liver disease every year.

The inverse relationship between coffee and cirrhosis was first reported by researchers at Kaiser Permanente in 1993. Subsequently, several other studies confirmed that coffee drinkers are less likely to have high levels of enzymes in the liver. Those liver enzymes can be markers for inflammation or indications of other problems, including disease. The biggest apparent protective benefits were among those who consumed the most alcohol.

The researchers say, because they did not see a similar protective effect among tea drinkers, there may be something in coffee other than just caffeine that helps protect against alcoholic cirrhosis.

This study was supported by a grant from the Kaiser Foundation Research Institute. Data collection from 1978 to 1985 was supported by a grant from the Alcoholic Beverage Medical Research Foundation, Baltimore.