Men's Health: Yo-Yo Dieting May Give You Gallstones
Men who repeatedly lose weight and gain it back are raising their risk of gallstones, according to a large study published this week in the Archives of Internal Medicine. The findings confirm those of a similar study in women and suggest that "weight cycling" should join rapid weight loss and obesity as risk factors for gallstone disease.
Researchers followed a total of 24,729 men over a 10-year period and found a correlation between the size of the weight fluctuation and the magnitude of added risk. Men who tended to lose and gain 5 to 9 pounds had a 21 percent increased risk of gallstones compared with people who maintained a constant weight. Those in the 10-to19-pound range had a 38 percent increase, and people who cycled up and down by 20 pounds or more had a 76 percent increased risk.
Now that obesity, rapid weight loss, and weight cycling have all been implicated in gallstone formation, notes lead author Chung-Jyi Tsai, a gastroenterologist at the University of Kentucky Medical Center, it's clear that one of the best ways to avoid gallstones is to avoid becoming overweight in the first place. For people trying to lose weight, experts recommend losing it gradually and not skipping meals. Skipping meals decreases gallbladder contractions, which promote gallstone formation. Losing weight at the rate of 1/2 to 2 pounds per week is thought to be ideal, says coauthor Michael Leitzmann, an expert on gallstone disease who now is a nutritional epidemiologist at the National Cancer Institute.
Of the 20 million Americans with gallstones, only 20 percent realize they have them. But the little chunks of cholesterol, which range in size from a grain of sand to a golf ball, can cause stomach pain, belching, gas, chronic indigestion, and nausea. In severe cases, which usually result in surgery, gallstones can cause infection of the surrounding tissue and lead to excruciating stomach pain, fever, vomiting, and jaundice.
The mechanisms behind the link between weight cycling and gallstone formation are not clear. However, gallstones occur when bile, a digestive fluid stored in the gallbladder, is high in cholesterol. The authors theorize that erratic swings in body weight may lead to an extra accumulation of body fat, and an imbalance in the ratio of salts and cholesterol in the gallbladder.
The data were drawn from a large sample, but Tsai points out that 96 percent of study participants were white. So the results might not be applicable to the entire American population. Gender, physical inactivity, ethnicity, estrogen levels, diabetes, and cholesterol lowering drugs can also affect the risk of gallstones.