Gallstones are collections of solid crystals (predominantly cholesterol) in the gallbladder or in the bile ducts (biliary tract). Americans undergo more than 800,000 gallstone operations each year and it is the most common abdominal illness seen among women in the US.
Researchers led by Chung-Jyi Tsai at the University of Kentucky at Lexington studied more than 42,000 women in 1986. All were between 39 and 66 years of age. At that time, none of them had had gallstones, reported the portal HealthCentral.
As part of the study, the women provided waist and hip measurements and details of their normal diet. Reporting in the Feb 13 online issue of Gut, the researchers found that nearly 3,200 of the women needed to undergo gallstone surgery by the year 2000.
Compared to women with waistlines at or under 26 inches, women with waistlines of 36 inches or more faced double the risk of developing gallstones requiring surgical removal, the researchers found.
In addition, a higher waist-to-hip ratio -- a calculation of waist size divided by hip size -- also increased the risk of gallstones. Women with a ratio of 0.86 were 40 percent more likely to have gallstones compared with women whose ratio was 0.70 or less.The study shows that widening waistlines are an important risk factor for gallstones in women.
'This is a way of fine-tuning obesity-related causes of gallstones,' said Joanne A.P. Wilson, a professor of gastroenterology at Duke University. A bulging midriff is also associated with a risk of heart disease, she added.
'The bottom line is that women should control their weight,' Wilson said.