Jumping for Soy
Nancy Clark, MS, RD
THE PHYSICIAN AND SPORTSMEDICINE - VOL 26 - NO. 4 - APRIL 98
Years ago, folks had little good to say about soy foods. Tofu, which is made from soy, was maligned as a food for "nutty" vegetarians. Textured vegetable protein, a soy-based meat extender, was called "mystery meat." Today, however, people are jumping for soy as the benefits of soy foods are recognized. Here is information to help you understand the health and nutritional power of soy, along with tips to help you add more soy to your diet.
Soy For Health
Reduced risks of some diseases have been documented in populations that consume a soy-rich diet. For example, Japanese and Chinese people have lower rates of heart disease and breast and prostate cancer than Americans. Soy may be one part of the explanation. Soy may also benefit menopausal women.
Heart disease. Soy may halt the chain of events that leads to clogged arteries. Research suggests that soy foods help lower cholesterol. And it appears that the higher the initial cholesterol level, the more effective soy is in reducing it.
Saturated fat and cholesterol in the diet are reduced when animal proteins are replaced with soy protein. Also, soy is rich in a polyunsaturated fat called linoleic acid, which has been shown to lower blood cholesterol.
Cancer. Soy is a rich source of phytochemicals—plant substances that may have health-promoting properties. Genestein, one of the phytochemicals in soy, may suppress the growth of tumor cells. Soy may reduce the risk of prostate cancer in men and the risk of breast cancer in women.
Soy is also one of the richest sources of plant estrogens. These substances can lengthen the menstrual cycle by 2 or 3 days. Over the course of a lifetime, this can reduce the potentially cancer-causing effects of the body's estrogens.
Menopausal concerns. During menopause, when a woman's estrogen production is declining, soy can provide some hormones and may reduce hot flashes. Although understanding of the physiologic effects of soy's estrogens is still limited, menopausal women may enhance—and will certainly not hurt—their overall health by including more soy in their diets.
Soy for Nutrition
Protein. Vegetarian diets are popular among active people, and soy's high-quality protein provides them with all the amino acids essential for building muscles. This means soy is an excellent alternative to animal protein.
Calcium. A bonus for tofu eaters is calcium, a mineral important for strong bones (see "All About Tofu," below). One-quarter cake of tofu (about 4 ounces) can offer up to 120 milligrams of calcium, the amount in 3 ounces of milk. Be sure to read the label to verify that the tofu has been calcium-coagulated; otherwise it will be a poor source of calcium.
In general, other soy foods are poor sources of calcium. If you drink soy milk instead of cows' milk, select a calcium-fortified brand.
Adding Soy to Your Diet
For most eat-on-the-run active people, the trick to boosting soy intake is boosting availability. But even though soy food is becoming tastier and more convenient, soy is far from mainstream. Even so, you can find soy foods if you know where to look.
You can find tofu in many ethnic restaurants. Soy is a common ingredient in Chinese, Thai, Indian, and other Asian cuisines. Soy foods are also found at vegetarian and "natural food" eateries. Elsewhere, search menus for garden burgers or veggie burgers.
When shopping, look for frozen soy products such as garden burgers, soy "crumbles" (small chunks similar to ground meat), and soy sausage patties or links in larger grocery or natural food stores, or buy soy protein powder at a health food store. Other common soy foods include soy dogs and tempeh (a meatlike patty). By trying different brands, you'll likely find several products you enjoy.
At home, including more soy in your diet takes conscious menu planning. (For help with this worthwhile effort, see "Tips for Enjoying Soy," below.) But soy can be quick and easy to prepare; tofu, for example, does not even need to be cooked.
One key to enjoying soy is to appreciate it for what it is. For example, even though a veggie burger looks like a hamburger, it won't measure up if you expect it to taste like one.
How Much Is Enough?
Research on cholesterol reduction demonstrates improvement with 30 or more grams of soy protein per day. You can get about 10 grams in 4 ounces (1/4 cake) of tofu, 8 ounces of soy milk, or one soy protein bar.
Because any soy is better than no soy, simply try to eat at least one serving a day. And remember, you need to eat soy in combination with an overall healthful diet. Double the joy of soy by eating other nutritious foods like fruits, vegetables, fiber, and healthful oils.
All About Tofu
Tofu is made when the milk-like liquid from soybeans is curdled and pressed into a solid block. Tofu has a custard-like texture, and on its own it is relatively flavorless. It gets its flavor from surrounding seasonings like soy sauce, curry, hot peppers, turmeric, or garlic.
Look for tofu in the produce section. It is sold in tubs or small boxes and comes in three main styles: silken, soft, and firm; the last holds its shape best. In general, the firmer the tofu, the more protein and calcium. Larger grocery stores may also sell herbed tofu.
Tofu often comes packed in water, and once you've opened the package, you should change the water daily to keep it fresh in your refrigerator.
Tips for Enjoying Soy
For More Information
For recipes and answers to your questions about soy and soy products, you can call the United Soybean Board at 1-800-TALK-SOY (1-800-825-5769) weekdays between 8 am and 4 pm CST. Its Web address is https://www.talksoy.com.
Remember: You, your physician, and your nutritionist need to work together to discuss nutrition concerns. The above information is not intended as a substitute for appropriate medical treatment.
Ms Clark is director of Nutrition Services at SportsMedicine Brookline in the Boston area. She is a fellow of the American College of Sports Medicine, a fellow of the American Dietetic Association, and a member of its practice group, Sports and Cardiovascular Nutritionists (SCAN).
Copyright (C) 1998. The McGraw-Hill Companies. All Rights Reserved