First discovered by Chinese monks nearly 5,000 years ago, soy is a complete protein containing eight essential amino acids. Soybeans also contain high levels of substances called isoflavones. Genestein, one of its major isoflavones, may help to reduce the risk of osteoporosis, cancer, and heart disease.
Soy enjoyed a surge in popularity in the 1960s when it became a staple of vegetarian diets. Now it's set to show up in more and more kitchens as a result of new health claims approved by the US Food and Drug Administration (FDA).
FDA Recommendation
As a result of a recent FDA decision regarding soy protein, food labels may now contain messages such as "25 grams of soy protein a day, as part of a diet low in saturated fat and cholesterol, may reduce the risk of heart disease."
The FDA is recommending that we incorporate four servings of at least 6.25 grams of soy protein into our daily diet. How to do that? No longer limited to health food stores, soy products are available in your local market--from tofu to soy-based burgers, "hot dogs," "chicken" products, breakfast patties and links; soymilk; soy cheese; soy flour; texturized soy protein (soy crumbles); soy protein bars; tempeh; roasted soy nuts; soybeans … there's no shortage of soy available.
Soybean farmers are anticipating a dramatic increase in soybean demand in the next 5 years, up from about 37 million bushels to more than 60 million bushels a year.
Versatile
Soy is a versatile food product and can be added to many recipes. Substituting soymilk for evaporated milk, blending soft tofu in dressings and sauces, thickening gravies with soy flour, and baking with soybean oil are all easy ways to add soy to your diet.
"There really are some benefits to soy," says Marjorie Geiser, a registered dietitian in Southern California. In addition to the cholesterol-lowering effects, there is the possibility that soy may help decrease a woman's chance of developing breast cancer.
Genestein, one of soy's major isoflavones, may help to reduce the risk of osteoporosis, cancer, and heart disease.
"Breast cancers are usually what are called 'estrogen dependent,'" says Geiser, "and it's believed that soy protein works as a 'phytoestrogen,' where it will bind to the receptor sites, helping prevent our body's own estrogen from attaching to these sites."
Although the research in this area is not yet conclusive, says Geiser, many nutrition experts are nonetheless recommending that women add some daily intake of soy products, usually in as natural a form as possible. "Because it's not just the isoflavones that are beneficial," Geiser observes. "We still don't know the effects of taking soy products in tablets or powder."
Diana Dyer, a registered dietitian in Ann Arbor, Michigan, is herself a two-time breast cancer survivor (as well as the survivor of a rare childhood cancer). After her most recent diagnosis 5 years ago, she decided to change her diet to incorporate soy.
"The data regarding soy and breast cancer is hardly unequivocal," Dyer admits, but adds that there are enough "clues" to warrant including a moderate amount of whole soy foods in one's diet.
Dyer voices some concern, however, that with the increasing number of soy products on the market, consumers may be adding soy in the wrong form. "Soy doughnuts, for example," she says, "aren't necessarily going to help you along the path to a healthy lifestyle if you're not going to reduce the amount of fat in your diet."
There is also evidence--although again, not conclusive--pointing to the benefits of soy in preventing prostate cancer, Dyer adds, and she has encouraged her husband and two teen-age sons to include soy in their diets as well.
As for helping with menopausal symptoms, Marjorie Geiser adds, there is no hard evidence to support this, but some women swear by it. "At the moment the research hasn't shown it to really help," she says, "but it certainly doesn't hurt to try."
