Reducing the risk of gallstones by eating a diet high in fiber, particularly the “insoluble” type found in whole-wheat products and corn bran, may help women avoid gallbladder surgery, new research suggests.

In fact, the protective effect of a high-fiber diet remains even after taking into account other risk factors for gallstones, Dr. Chung-Jyi Tsai, at Harvard Medical School in Boston, and colleagues found.

These findings, published in the American Journal of Gastroenterology, appear shortly after a report from the same research team showing that consumption of vegetable protein also seems to block gallstone formation.

Tsai’s group analyzed data from approximately 70,000 women who completed food-frequency questionnaires starting in 1984. The women were apparently free from gallbladder disease when the study began.

By 2000, nearly 6000 of the women had undergone gallbladder removal, also called cholecystectomy. Women who consumed the highest amounts of fiber were 13 percent less likely to undergo cholecystectomy than those who consumed the lowest amounts. The reduction in risk was even more pronounced for the highest levels of insoluble fiber intake -17 percent.

The authors note that fiber has a number of biochemical effects that may reduce gallstone formation.

“Our findings support the notion that the public should consume adequate amounts of dietary fiber,” Tsai and associates conclude.

SOURCE: American Journal of Gastroenterology, July, 2004.