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Soy—So good for your heart?

There’s been a lot of news about the heart-healthy attributes of soy. Amid all the hype and headlines, it’s hard to sort out if and how soy can make a difference. It can help—but it’s important to understand what it can and can’t do.

The claims

Soy protein comes from the soybean, a staple of Asian cuisine, and is found in tofu, soy flour and soy milk. (Soy sauce, however, contains only a trace of soy and a lot of sodium!) Experts have long speculated that the high soy intake in Asian countries may somehow correlate with their low levels of heart disease.

Studies indicate that eating an average of 47 grams of soy a day lowers LDL cholesterol (the bad kind) by 13 percent, total cholesterol by 9 percent and triglycerides by 10 percent. Yet HDL cholesterol (the good kind) remains constant.

Why soy improves cholesterol levels remains unclear. One strong theory is that the effect may be triggered by plant hormones abundant in soy. These hormones are similar to human estrogen, which accounts for the low risk of heart disease among premenopausal women.

Hold on …

Before you stock up on soy products, keep in mind that the studies that produced such heartening results were based on diets unusually high in soy protein. To consume 40 to 50 grams daily of soy protein, you would have to eat at least six servings of tofu or drink six glasses of soy milk every day—not a typical American diet and not a practical goal.

What about soy supplements and powders? They may be worth exploring, but many have other ingredients mixed in that may counter the positive effects. Some, in fact, skimp on the expensive hormones that are the probable potent ingredients, while others are processed in such a way as to wash out the hormones.

Part of a heart-healthy diet

So, skip soy? Well, not exactly. Soy, even without the possible cholesterol-lowering effects, is worth a second look if you’re trying to eat in a heart-smart manner.

Since the American Heart Association recommends a diet based less on animal fat and more on fruits and vegetables, tofu can be a great way to achieve those dietary goals. Soy protein is low in saturated fat and is cholesterol free, yet is equal in nutritional value to animal protein. Soy can substitute for some of your animal-based proteins if you’re a meat eater or be a major source of protein if you’re a vegetarian.

Once you get the knack of cooking with soy, you may well develop a taste for it. Silken soy can be pureed to form the basis of many fat-free dressings, dips and shakes. Firm soy takes on the flavors and nuances of ingredients it’s cooked with and can substitute as meat in pasta sauces, soups and stir-fries.