Breast Cancer Risk: Do Genes Determine Diet's Effect?

A new study published in the American Journal of Epidemiology shows that the power of fruits and vegetables to protect against breast cancer may depend on a woman’s genes. The Long Island Breast Cancer Study Project included 1,008 women newly diagnosed with breast cancer and 1,056 women without cancer. Each woman was typed for the genes that code for the catalase enzyme, an endogenous antioxidant enzyme that eliminates potentially cancer-causing free radicals by converting them to water and oxygen.

It turned out that women who had a specific catalase gene type, called CC, who also consumed ten or more servings of fruits each week had a 29 percent reduction in risk. However, women who ate plenty of fruits and vegetables but had different catalase gene variants had somewhat less protection from a healthful diet, suggesting that genetic factors influence diet’s effect.