What do steak, tofu and sushi have to do with cancer? Plenty, it seems, if several new studies served up at the American Association for Cancer Research in Boston are to be believed. And not all bear good news: the latest report from the sprawling Nurse's Health Study, for example, detected an unsettling association between red meat and breast cancer.
The report that interested me most looked at the association between breast cancer and soy-based foods. This is a controversial topic because soy contains isoflavones, some of which in isolated form can stimulate the growth of estrogen-receptor-positive breast-cancer cells. That's why many Western doctors...