- An Italian study4 with 1962 participants and 104 new cases of gallbladder disease (diagnosed by ultrasonic or X-ray techniques) reported an inverse association between coffee consumption and gallbladder disease
- The Health Professional Follow-up Study (HPFS)5 with 46,008 male participants and 1081 new cases (also diagnosed by ultrasonic or X-ray techniques), reported a relative risk of 0.6 in men who drank 2-3 cups of coffee per day and a relative risk of 0.55 in those who drank 4 or more cups per day. In other words, men who drank 2-3 cups of coffee a day had a 40% lower risk of symptomatic gallstones, and those who drank 4 cups or more had a 45% lower risk, than those who drank no coffee. The authors conclude: “In this cohort of US men, coffee consumption may have helped to prevent symptomatic gallstone disease”
- The Nurses Health Study (NHS)6 with 89,898 female participants and 7,811 cases of cholecystectomy (surgery to remove the gallbladder) reported a relative risk of 0.91 for women who drank one cup of coffee per day, a relative risk of 0.78 for those who drank 2-3 cups per day and a relative risk of 0.72 for those who drank four or more cups per day. In other words, women who drank 1 cup of coffee a day had a 9% lower risk, those who drank 2-3 cups had a 22% lower risk, and those who drank 4 or more cups a day had a 28% lower risk than those who drank no coffee. The authors conclude: “These data suggest that consumption of caffeinated coffee may play a role in prevention of symptomatic gallstone disease in women”
- An American study7 with 16,785 male participants and 685 new cases used “self-reported physician diagnosed” as the diagnostic criterion. Moreover, in this particular study, coffee was not consistently included throughout the study in the food questionnaires, and when it was, participants answered a yes/no question only, i.e. there was no measure of the amount of coffee consumed. This study was the only one of the four prospective cohort studies not to observe an association between coffee consumption and gallstones
Both the HPFS and the NHS also found an inverse association between caffeine intake and gallbladder disease, but no statistically significant association for decaffeinated coffee.
- In contrast, an Italian case-control study8, with 195 new cases requiring surgery and 1122 hospital controls, did not show an association for coffee consumption8.
- Similarly, a US cross-sectional study9 examined 13,938 participants for total gallbladder disease by ultrasound or evidence of cholecystectomy. They evaluated total gallbladder disease, as well as previously undiagnosed (~non-symptomatic) and previously diagnosed (~symptomatic) gallbladder disease. They found no associations between coffee consumption and gallbladder disease for both total and previously undiagnosed gallbladder disease in either men or women. They did find an inverse association between coffee consumption and previously diagnosed (~symptomatic) gallbladder disease in women only. The authors conclude: “These findings do not support a protective effect of coffee consumption on total gallbladder disease, although coffee may decrease the risk of symptomatic gallstones in women”
Overall, allowing for relative strengths and weaknesses of the studies reviewed, results* show a negative association between coffee consumption and the risk of symptomatic gallstones. Coffee consumption may play a preventive role.