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The Benefits, Risks, and Uncertainties of Soy for Lower Blood Cholesterol
Soy and Cholesterol Levels
Soy Safety Issues
- 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.
- Lowe testosterone levels—One study found that soy may decrease testosterone levels in men. This could potentially cause problems with infertility or erectile dyfunction.
- Problems with absorbing certain nutrients—Soy could reduce how well your body absorbs zinc, iron, and calcium.
Ways to Get More Soy Into 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 http://www.americanheart.org/
National Heart, Lung, and Blood Institute http://www.nhlbi.nih.gov/
Dietitians of Canada http://www.dietitians.ca/
Health Canada http://hc-sc.gc.ca/
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Indiana Soybean Board. The US Soyfoods Directory. Stevens & Associates, Inc. Indianapolis, IN; 2002.
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Sacks FM, Lichtenstein A, Van Horn L, Harris W, Kris-Etherton P, Winston M; American Heart Association Nutrition Committee. Soy protein, isoflavones, and cardiovascular health: an American Heart Association Science Advisory for professionals from the Nutrition Committee. Circulation. 2006;113(7):1034-44.
Soy. EBSCO Natural and Alternative Treatments website. Available at: http://www.ebscohost.com/healthLibrary/. Updated August 2011. Accessed July 12, 2012.
12/17/2009 DynaMed's Systematic Literature Surveillance DynaMed's Systematic Literature Surveillance: Shu XO, Zheng Y, Cai H, et al. Soy food intake and breast cancer survival. JAMA. 2009;302:2437-2443.
- Reviewer: Brian Randall, MD
- Review Date: 07/2012
- Update Date: 07/11/2012