Coffee consumption linked to gallbladder contraction

Research indicates that coffee consumption causes the gallbladder to contract, a process driven by the release of the hormone cholecystokinin. This effect occurs with both regular and decaffeinated coffee, suggesting that caffeine is not the sole cause. In studies, regular coffee caused an average contraction of 33 percent, while decaffeinated coffee caused a 29 percent contraction, compared to only 10 percent for a saline solution.

While this contraction is generally not an issue for healthy individuals, it can cause pain for those who already have gallstones. Experts note that coffee is not the strongest trigger for gallbladder contraction; fatty emulsions and semi-skimmed milk have been shown to cause even stronger contractions.

Conversely, large-scale studies suggest coffee may have a protective effect. A Danish study involving over 104,000 participants found that individuals drinking more than six cups of coffee daily had a 23 percent lower risk of gallbladder issues compared to non-consumers. Major risk factors for gallstones remain obesity, type 2 diabetes, and smoking.