I've received a lot of mail from readers asking about that New York Times article. For those of you who didn't see it, let me recap briefly: The Times reported a growing concern from the scientific community that components of soy, called isoflavones, may raise the risk of certain cancers -- particularly for post-menopausal women who have been encouraged to increase the amount of soy in their diets as a substitute for estrogen replacement therapy.Soy isoflavones are phytoestrogens (that is, plant estrogens) that can act in the body the same way as estrogens in hormone replacement therapy (HRT). Theoretically, isoflavones can help relieve menopausal symptoms such as hot flashes -- and like HRT, increase a woman's risk of breast cancer. What's become worrisome is that, instead of eating more tofu, Americans are buying soy pills and supplements which contain isolated isoflavones. According to the Times article, in a one-year period ending in October 1999, sales of isoflavone pills jumped by 246 percent. The Times article focused on isoflavones found in both soy supplements and soy foods -- but I believe whole soy foods, such as tofu, tempeh, edamame (green soy beans in the pod), miso, and other unrefined soy foods are safe. Getting an isolated compound is a different story: No one can say with any certainty how large doses of soy isoflavones will affect the body. And even the researchers interviewed for the Times article made the point that you're unlikely to get too many isoflavones as a result of adding soy foods to your diet -- but you probably will take in too much if you take soy supplements in pill form. At this point, I can only recommend that you avoid soy supplements entirely. The Times article pointed out that conflicting studies on the safety of soy are another confusing issue. The article mentions a study, published in the American Journal of Clinical Nutrition in December 1998, which showed increased breast cell proliferation among women eating soy foods. (This cell proliferation can increase the risk of breast cancer.) But other epidemiological studies contradict these findings: Populations that eat a lot of soy foods -- the Japanese, for instance -- have low rates of breast and prostate cancer. Until we have more definitive research, my guess is that the benefits of soy foods outweigh the risks. The Food and Drug Administration seems to agree. In October 1999, they authorized food manufacturers to say on food labels that soy protein could help lower cholesterol and reduce the risk of heart disease. The foods eligible to make the health claim -- soy beverages, tofu, tempeh, soy-based meat alternatives, and some baked goods -- must also be low in fat, saturated fat, and cholesterol. What's important to remember here, though, is that the FDA allows this claim for soy protein -- not isoflavones. So should those who have had breast cancer, or are at high risk for the disease, eat soy? The scientific evidence isn't in yet, but I can offer my opinion: I believe the phytoestrogens in soy protect estrogen receptors from excessive stimulation by the body's own hormones and foreign estrogen-like substances. Therefore, I recommend it. And if you have high cholesterol or a family history of heart disease, I think it's definitely worth your while to include some soy foods in your diet.