Coffee Lowers Risk of Gallstone Disease in Women

Women who consistently drink four cups of caffienated coffee a day have significantly lower risk of gallstone disease than those who do not drink coffee, researchers report in the December issue of the American Gastroenterological Association's journal Gastroenterology.

The Harvard Nurses' Health study followed 80,898 women for twenty years and tracked their coffee intake and whether they had surgery to remove the gallbladder. During the follow up years, 7,811 women had gallbladder surgery. The rate of surgery for coffee drinkers was about 25 percent less than the rate for those who did not drink coffee.

"Women should not start drinking coffee just to prevent gallstone disease," says Michael F. Leitzmann, MD, lead author of the study who is now an Investigator at the National Cancer Institute. "However, if a woman already happens to be a coffee drinker, our study suggests that it is okay for her to continue drinking coffee in terms of her risk of gallstone disease."

Almost half of all Americans drink coffee, amounting to a per capita intake of 1.7 cups a day. In the study, all brewing methods showed a decreased risk of gallbladder surgery. Protection from gallstone disease increased with increasing coffee consumption, up to four cups per day. Those who drank five or more cups of coffee further decreased their risk of gallstone disease beyond that of women who drank four cups daily.

"It appears that caffeine may be the protective ingredient in coffee that is responsible for the decreased risk of gallstone disease among coffee drinkers," notes Dr. Leitzmann. "There is experimental evidence from other studies showing that caffeine leads to gallbladder contractions, which could theoretically help prevent the formation of gallstones in the gallbladder."

Women are twice as likely to develop gallstones than men are. Women who are overweight and those who undergo rapid weight loss have a particularly increased risk. The research team previously showed that men who drink coffee have a lower risk of gallstone disease than those who do not drink coffee. The current findings in women are very similar to earlier results among men*.

The Nurses' Health Study, established in 1976 by Dr. Frank Speizer and the Nurses' Health Study II, established in 1989 by Dr. Walter Willett, are among the largest prospective investigations into the risk factors for major chronic diseases in women. In the Nurses' Health Study, 121,700 married female nurses aged 30 to 55 years completed a mailed questionnaire on their medical history and lifestyle characteristics in 1976. Every two years, follow-up questionnaires were sent to update information on potential risk factors and to identify newly diagnosed illnesses. In 1980, the questionnaire included an extensive assessment of diet. This analysis is based on the 80,898 women who answered the 1980 diet questionnaire and did not have cancer, a cholecystectomy (gallbladder surgery), or a gallstone diagnosis before 1980.

Gastroenterology is the official journal of the American Gastroenterological Association, the oldest non-profit specialty medical society in the United States with a membership of almost 13,000 physicians and researchers. Gastroenterology is the most prominent journal in the subspecialty and is in the top one percent of indexed medical journals internationally. Gastroenterology is published monthly.

*Leitzmann et al. JAMA 1999; 281:2106-12