For the past several decades, millions of American women have managed the symptoms of menopause with hormone replacement therapy (HRT). Until very recently, many of them also thought they were gaining protection against heart disease by taking HRT. But last summer's widely reported findings of the Women's Health Initiative combination-HRT study--which show a correlation between use of an estrogen-progestin hormone supplement and serious illnesses such as stroke, breast cancer, and heart disease--has inspired many women to search for alternative methods to cope with the symptoms of menopause.

Among various nutritional supplements and foodstuffs that are touted as natural ways to manage menopause, soy is probably the best known. Soy has gained special prominence in recent years as a rich source of isoflavones--an estrogen-like substance found in plants that produces, in a weaker form, many of the same effects that human estrogen does. Many studies confirm that regularly eating moderate amounts of soy-based food products can help decrease menopausal symptoms--supporting soy's value as a dietary approach to estrogen replacement.

However, a note of caution: Even natural products are not risk-free, especially when taken in large amounts. Soy contains variable amounts of chemicals known as "anti-nutrients" that interfere with digestive processes and absorption of other essential nutrients, such as zinc and calcium. Also, the hormonal activity of soy isoflavones may, just like HRT, stimulate estrogen-mediated diseases such as breast and ovarian cancer and we do not know what impact that may have on risk of those diseases, especially in certain high-risk subgroups of women. So don't go overboard: Shoot for several servings of soy a week, rather than multiple helpings each day. Some other tips to keep in mind:

Soy products vary widely in the amount of processing they have been subjected to. For general nutritional purposes and cardiovascular benefits such as lowering blood cholesterol levels, whole soy foods such as tofu, soy milk, and edamame (young fresh or frozen soybeans) are preferable to more highly processed varieties, such as textured vegetable protein. Fermented soy foods such as miso and tempeh are especially nutritious and easy to digest, as the fermenting process inactivates many of the anti-nutrients.

If your main interest in incorporating soy into your diet is the hormone-like effects of its isoflavones on menopause symptoms or heart disease risk, it doesn't really matter how you get them. The main point is to get a blood level of isoflavones that works for you. "Smoothies" made with soy milk and/or soy powder are an efficient way to ingest isoflavones. Isoflavone supplements used in moderation are another way to get isoflavones.

Because people react differently to soy, have varying family risk factors, and may be taking it for different reasons, no standard dosage has been identified that will work for everyone. To decrease hot flushes, studies suggest that you may need one to four servings of soy-based foods per day, for a total of about 40 to 50 milligrams of soy isoflavones per day. For heart benefits, the FDA suggests an intake of 25 grams of soy protein each day. Soy foods can cause gas and intestinal discomfort, so add them to your diet slowly--try one new type of soy food per week.

While soy on its own is quite bland, it absorbs the flavors of other ingredients readily, making it easy to incorporate into many dishes. Try using soy milk on cereals and in soups and puddings; adding small cubes of tofu to soups, stews, and pasta dishes; substituting silken tofu for ricotta or cottage cheese in casserole recipes; using textured vegetable protein as a substitute for ground beef or ground turkey in chili, meat sauces, or meat loaf; or using soy flour to replace part of the wheat flour called for when making cookies, muffins, or bread.

Some menopausal women find that soy alone won't alleviate certain symptoms--in particular, stubborn and severe hot flushes. I typically recommend that patients who are troubled by such symptoms use the lowest possible dose of prescription steroidal estrogen that will control them. Often, incorporating soy into the diet has the effect of complementing HRT and making it possible for women to do well on a lower dose of the prescribed estrogen.

To be most effective in easing the symptoms of menopause and contributing to a longer and healthier life, adding soy to your diet should be accompanied by other beneficial lifestyle changes, such as eating a nutritious, high-fiber diet, limiting alcohol intake, exercising daily, quitting smoking, and managing stress.

The bottom line: We evolved as omnivores, and we're designed to eat a little bit of a lot of different foods. Soy has a helpful role to play in managing menopausal symptoms and maintaining health--especially when used in moderation and within the context of a healthy lifestyle and balanced diet.

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