The Benefits, Risks, and Uncertainties of Soy for Lower Blood Cholesterol
Soy, a type of legume, can be found in many products. On the grocery store shelves, you will see soy milk, tofu, protein bars, veggie burgers, and many other options. Are you interested in adding soy to your diet? Are there health benefits? Find out if soy is a good option for you.
Soy and Cholesterol Levels
Some studies have found that substituting soy protein for high-fat meats and other foods may reduce LDL "bad" cholesterol levels. Since high cholesterol puts you at an increased risk of developing heart disease, the Food and Drug Administration (FDA) allows a "heart healthy" label on foods that contain 6.25 grams (g) of soy protein. But, researchers do not know the exact components of soy that may lead to these benefits. And some experts are debating if this label is deserved at all.
Soy Safety Issues
While soy is considered safe for most people, there are some health concerns if you have certain conditions, such as:
- Impaired thyroid function—Soy may affect the thyroid gland, but research had produced conflicting results. In general, if you have problems with your thyroid gland, it is a good idea to avoid eating large amounts of soy.
- Infertility or erectile dyfunction—One study found that soy may decrease testosterone levels in men.
- Problems with absorbing certain nutrients—Soy could reduce how well your body absorbs zinc, iron, and calcium. You may want to take these supplements a couple of hours after eating soy.
If you are concerned about any of these safety issues, talk to your doctor before adding soy to your diet.
Ways to Get More Soy Into Your Diet
Here are some tips on substituting soy protein for meats and other protein sources in your diet:
- Mash a cake of tofu and use it in place of ricotta cheese in your lasagna.
- Mix textured vegetable protein into hamburgers and seasoned meat dishes like tacos, chili, and casseroles.
- Add cubes of fried, seasoned tofu to salads.
- Try Asian cuisine.—Japanese, Chinese, Thai, and Vietnamese foods often contain flavorful soy options, including tofu, tempeh, and edamame (green soy beans). Edamame is eaten cold and salted. Tofu and tempeh can be stir-fried, steamed, or added to soups.
- Use supplements and soy protein powders.—Try mixing soy protein powders into smoothies or mashed potatoes.
- Soy nuts, flavored with salt and spices, make a delicious snack.
- Use soymilk in cereal.
Major Food Sources
|Soy Food||Serving size||Soy content (grams)||Isoflavones (milligrams)|
|Soybeans, cooked||½ cup||9-11||40-50|
|Soy milk (regular)||1 cup||7||10|
|Soy milk (fortified)||1 cup||10||43|
|Textured soy protein||¼ cup||11||33|
|Isolated soy protein||½ ounce||11||27|
|Meat alternatives (soy crumbles)||½ cup||11||8.5|
American Heart Association
National Heart, Lung, and Blood Institute
Canadian Council on Food and Nutrition
Dietitians of Canada
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Last reviewed June 2010 by ]]>Brian Randall, MD]]>
Please be aware that this information is provided to supplement the care provided by your physician. It is neither intended nor implied to be a substitute for professional medical advice. CALL YOUR HEALTHCARE PROVIDER IMMEDIATELY IF YOU THINK YOU MAY HAVE A MEDICAL EMERGENCY. Always seek the advice of your physician or other qualified health provider prior to starting any new treatment or with any questions you may have regarding a medical condition.
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