Higher BMI increases risk of gallstones
Obesity has long been associated with gallstone risk, especially in women. Researchers have suggested a few possible reasons for this connection, including that people who are overweight produce more cholesterol, which triggers stone formation. Yet it's been unclear whether a high body mass index (BMI) or factors associated with being overweight—such as a high-fat diet and lack of exercise—are to blame for gallstones. Researchers in Denmark used gene variants related to high BMI to isolate whether BMI itself is responsible for gallstone formation. The authors looked at more than 77,000 people over a 34-year period. About 4,100 of them developed gallstones during that time. Those who developed gallstones were more likely to be older, female, and less physically active. Women with a high BMI were nearly three times as likely to develop gallstones as those with a healthy BMI. People who were genetically predisposed to have a high BMI were more likely to have gallstones. The authors say this study confirms that obesity itself, as well as factors that lead to obesity, increases the risk of gallstones.