No matter what your taste preference, a soy food is available to satisfy your picky palate and cater to your cardiovascular well-being.

Annual sales of soy in the US continue to grow more than 10% a year, edging toward the $4 billion mark. Today, the average American consumes about 10 mg of soy protein a day, even though the American Heart Association (AHA) recommends taking in at least 25 mg of soy to benefit your heart. Even the Food and Drug Administration (FDA) has signaled its approval of the soy bandwagon, allowing claims that daily soy can help lower the risk of cardiovascular complications.

As Good as a Drug

Researchers who have investigated how soy can help lower cholesterol and shrink the risk of heart disease have concluded that soy, in a diet with fruits and vegetables, can be as effective as cholesterol-reducing drugs (JAMA 7/22/03).

Researchers at the University of Toronto and St. Michael's Hospital compared the cholesterol-lowering power of soy and other vegetarian foods with that of lovastatin, a standard pharmaceutical used to reduce cholesterol.

In the study, scientists fed people a diet that, along with soy, had large amounts of nuts, such as almonds and walnuts, and high-fiber foods like oats and barley plus margarine made with plant sterols (natural substances derived from leafy greens and vegetable oils). Researcher David Jenkins, PhD, a nutrition science professor, thinks these foods may be good at dropping cholesterol because human evolution makes us well-adapted for an "ape diet," one high in fiber, vegetable protein, nuts and plant sterols.

According to Dr. Jenkins, "As we age, we tend to get raised cholesterol, which in turn increases our risk of heart disease. This study shows that people now have a dietary alternative to drugs to control their cholesterol, at least initially." Dr. Jenkins also thinks that soy and a vegetarian diet can be used to maintain normal cholesterol levels.

Soy Meals

Dr. Jenkins' heart-healthy diet, designed to be easily prepared and consumed, includes oat bran bread and cereal, soy drinks, fruit and soy deli slices. For instance, in his study, a typical dinner consisted of tofu baked with eggplant, onions and sweet peppers, pearled barley and vegetables.

Dr. Jenkins adds, "The Food and Drug Administration has approved these cholesterol-lowering foods as having legitimate health claims for heart disease risk reduction. They're also being recommended by the American Heart Association and the National Cholesterol Education Program as foods that should be incorporated into the diet. And we have now proven that these foods have an almost identical effect on lowering cholesterol as the original cholesterol-reducing drugs."

Dr. Jenkins regrets that health practitioners often give drugs to people with high cholesterol instead of trying to control the problem with soy and other vegetarian foods.

Soy Safety Affirmed

Recently, some doctors have spread the story that soy may increase the risk of cancer because natural chemicals in soy act like estrogens, hormones that may contribute to breast and other cancers. However, research has failed to support this supposition.

As Dr. Jenkins points out, "the concerns have been whether soy estrogen might lead to hormone-dependent breast cancer or abnormal sexual development in children, yet we found no evidence to support this."

In another of Dr. Jenkins' studies, people were put on diets high in soy to see how their estrogen levels were affected. Then, the researchers measured estrogen byproducts in their urine. Since estrogen stimulates breast cancer cells to produce a special protein, the researchers measured the amount of this protein produced by each urine sample to calculate how much estrogen was present.

The total estrogenic activity in the urine of women on soy dropped to lower levels than it had been before they ate soy. "This finding suggests that soy may not have the estrogenic effects that were thought to alleviate menopausal symptoms but it refutes claims about its purported hormone risks," Dr. Jenkins says.

The study also demonstrated that soy can reduce the risk of heart disease by lowering levels of oxidized cholesterol, which is thought to stick to coronary artery walls and form dangerous plaques. Dr. Jenkins' other research demonstrates that soy consumption reduces cholesterol in general while also decreasing the amount of LDL (bad) cholesterol in the body and maintaining the HDL (good) cholesterol. According to Dr. Jenkins, this confirms that soy should be promoted for its important role in preventing heart disease without fear that it will promote cancer.

In another study in China, researchers compared the dietary habits of more than 350 women with breast cancer to the foods eaten by more than 1,000 women who did not have cancer (Amer Assoc Canc Res Second Annual Intl Conf Fron Can Prev Res 10/27/03, Abst 1274). They found that eating large amounts of soy did not raise the risk of breast cancer.

Of course, anyone can develop allergies to almost any food, soy included. If eating soy causes you discomfort, find another source of healthy protein (see box on whey protein above).

Isoflavone Benefit

Isoflavones, soy's plant estrogens, are believed to create some of the most significant heart-healthy soy benefits. Consequently, researchers urge those concerned about their cardiovascular health to combine a diet high in soy, fruits and vegetables with exercise for the highest level of heart protection. Cheaper than cholesterol drugs, tastier than many other healthy foods and available in so many forms, soy's popularity will certainly continue to explode. Soy burgers, soy drinks and soy just-about-everything will continue to be a big part of our lives.