From Scientific American:
People who ate soy regularly as children have a lower risk of breast cancer, researchers reported on Tuesday. And men who eat fish several times a week have a lower risk of colon cancer, a second team of researchers told a meeting in Boston of the American Association for Cancer Research. The studies add to a growing body of evidence about the role of diet in cancer. Cancer experts now believe that up to two-thirds of all cancers come from lifestyle factors such as smoking, diet and lack of exercise.
Dr. Larissa Korde of the National Cancer Institute and colleagues at the University of Hawaii studied studied 597 Asian-American women with breast cancer and 966 women without the disease. The mothers of some of the women were also available to answer questions about what they fed their daughters as children. The women who ate the most soy-based foods such as tofu and miso when aged 5 to 11 reduced their risk of developing breast cancer by 58 percent, the researchers found. “Childhood soy intake was significantly associated with reduced breast cancer risk in our study, suggesting that the timing of soy intake may be especially critical,” Korde said. It is not clear how soy might prevent cancer, although compounds in soy called isoflavones have estrogen-like effects.
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