Sedentary office work can put women at risk of gallstones
US researchers have found that women who adopt a sedentary lifestyle are most at risk of developing gallstones.
Gallstones are tiny - but painful - deposits which form in the gallbladder, the organ which stores the digestive juice bile after it is manufactured by the liver.
The stones can be removed surgically, an operation known as a cholecystectomy.
It has long been recognised by the medical profession that people who are overweight are more at risk of developing gallstones.
Now researchers from Boston's Brigham and Women's Hospital have found that a sedentary lifestyle is also a risk.
Their study showed that women who exercised cut their risk of gallbladder surgery by 31%.
Big difference
The scientists found that for every 100 inactive women who needed surgery, just 69 active women required the same operation.
The findings, published in the New England Journal of Medicine, come from 60,290 questionnaires filled out by women in the Nurses' Health Study, a survey of more than 121,000 female registered nurses begun in 1976.
Women who spent 41 to 60 hours a week driving or sitting at work were 42% more likely to require gallbladder surgery than women who spent fewer than six hours in similar sedentary activities.
And for women who were driving or sitting for more than 60 hours, the rate of gallbladder removal was 132% higher than for active women.
The researchers, led by Dr Michael Leitzman, said: "An average of two to three hours of recreational exercise per week appeared to reduce the risk by about 20%."
In an accompanying editorial, Dr Kenneth Vega and Dr David Johnson said the work "confirms similar observation from a study in men".
However, they warned that one study did not establish cause and effect
Overweight people who want to avoid gallstones should try to lose weight, but do it gradually, as sudden weight loss can trigger gallbladder disease.