More coffee, fewer gallstonesBMJ 1999; 318 doi: https://doi.org/10.1136/bmj.318.7199.1646e (Published 19 June 1999) Cite this as: BMJ 1999;318:1646
Men who drink two to three cups of coffee a day have a 4% lower risk of developing gallstones than those who do not drink coffee regularly, and men who drink four or more cups a day have a 45% lower risk, according to a new study.
But only coffee with caffeine, which is known to stimulate contractions in the gallbladder and lower cholesterol concentrations in bile, was associated with the lowered risk. Caffeinated tea and soda did not have the same effect, the researchers reported.
The study, published by Dr Michael Leitzmann and colleagues at the Harvard School of Public Health, involved approximately 46 000 men drawn from the ongoing Health Professionals Follow Up Study, a prospective cohort study in which the consumption of coffee and other caffeinated drinks was assessed, starting in 1986, as part of a 131 item food frequency questionnaire given to male healthprofessionals in the United States.
Participants ranged in age from 40 to 75 years and had no history of gallstone disease when they entered the study. During the follow up period of 10 years, 1081 subjects reported symptomatic gallstone disease, of whom 885 required cholecystectomy. After adjusting for other known or suspected risk factors, the risk of symptomatic gallstone disease declined with increasing caffeine intake. (JAMA 1999;281:2106-2112).
Although coffee had been known to have several metabolic effects that could explain the reduction in gallstone formation, earlier studies of its effects had yielded mixed results. “We believe the association we saw between coffee intake and gallstone disease may be due specifically to the effect of caffeine,” Leitzmann said.
In the study, beverages that delivered lower doses of caffeine did not have the same beneficial effects as coffee. For example, the researchers found no similar effect among men drinking tea, decaffeinated coffee, or carbonated soft drinks.
“What we're talking about here is the prevention of gallstones,” Leitzmann said. “Coffee is of no help if you already have gallstone disease.” In fact, Leitzmann observed that drinking coffee has previously been associated with increased abdominal pain in people afflicted with gallstones.