Yo-Yo Dieting May Up Men's Gallstone Risk

(WebMD)  Yo-yo dieting may have another unhealthy and particularly painful side effect for men: gallstones.

A new study shows men who repeatedly lose, then regain 20 or more pounds through dieting are up to 76 percent more likely to develop gallstones later in life than men who maintain a constant weight.

Gallstones occur when a solid mass of cholesterol, bile, and calcium salts form in the gallbladder, often causing severe pain in the stomach area and requiring surgical treatment.

Obesity and rapid weight loss associated with dieting are known to increase the risk of developing gallstone disease, but researchers say the long-term effects of frequent weight fluctuation on gallstone risk in men hasn't been clear.

Yo-Yo Dieting Linked to Gallstones

In the study, published in the Archives of Internal Medicine, researchers analyzed data on nearly 25,000 men who participated in the Health Professionals Follow-up Study. The men provided information on weight fluctuations from 1988 to 1992 and were followed from 1992 to 2002 for gallstones.

The results showed gallstones were more likely in men whose weight fluctuated more than 5 pounds than those who maintained a constant weight, and the risk of gallstones increased with the degree of weight fluctuation.

For example:

• Men whose weight fluctuated between 5 and 9 pounds per dieting attempt were 21 percent more likely to have gallstones.
  
• Men who had a weight loss of between 10 and 19 pounds had a 38 percent greater risk.
  
• Men who lost 20 or more pounds per dieting attempt were 76 percent more likely to have gallstones.

Percentages above take into account other factors, such as age, physical activity, alcohol intake, smoking, dietary factors, and use of certain medications.

The risk of gallstones also increased with the number of yo-yo dieting attempts. Men who lost and regained weight more than once had nearly double the risk of gallstones when compared with men who maintained their weight.

Researcher Chung-Jyi Tsai, MD, ScD of the University of Kentucky Medical Center, Lexington, and colleagues say many factors associated with yo-yo dieting may work to raise the risk of gallstones, such as an increased concentration of cholesterol in the bile associated with rapid weight loss.

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SOURCE: Tsai, C. Archives of Internal Medicine, Nov. 27, 2006; vol 166: pp 2369-2374.

By Jennifer Warner
Reviewed by Louise Chang