High Protein Diets May Boost Cancer Risk

One expert also thinks that a high-protein diet increases the risk for certain cancers.

"We recently published a paper that also shows that a high-protein diet is bad for you. It reduces survival; it increases the risk of cancer," said Dr. Dimitrios Trichopoulos, the Vincent L. Gregory Professor of Cancer Prevention at the Harvard School of Public Health's Department of Epidemiology.

In that study, published online in the Nov. 29 issue of theEuropean Journal of Clinical Nutrition, the researchers collected data on the diets of 22,944 healthy adults and found that eating diets low in carbohydrates and high in protein was associated with increased mortality.

Trichopoulos thinks that levels of IGF-1 may be the reason for the increased cancer risk. However, other factors may be at work, he added.

Despite his and Fontana's findings, Trichopoulos isn't ready to recommend a low-protein diet to reduce the risk of cancer or to live longer. Another recent study contradicted this finding, Trichopoulos said. "At this stage, we should wait for clarification," he said.

More information

The American Cancer Society can tell you more about cancer and diet.

SOURCES: Luigi Fontana, M.D., Ph.D., assistant professor of medicine, Washington University, St. Louis, and investigator, Istituto Superiore di Sanita, Rome, Italy; Dimitrios Trichopoulos, M.D., Vincent L. Gregory Professor of Cancer Prevention, Department of Epidemiology, Harvard School of Public Health, Boston; December 2006,American Journal of Clinical Nutrition; Nov. 29, 2006, online edition,European Journal of Clinical Nutrition