Soy has gotten a bad rap over the last several years due to consumers believing it is to blame for a host of issues ranging from feminine features and low testosterone to breast cancer and poor nutrition. In reality, soybeans are a complete protein, just like animal-based products, and it has been shown to be protective against several health conditions and diseases. Let’s set the record straight for this mighty food.
You’re headed to the supermarket: where might you find soy? Soy is a legume made from the common soybean and can be filtered, roasted, or ground then made into a range of products. Soy is seen in tofu (soft and firm varieties), tempeh and miso (fermented soybean foods), edamame, soy sauce, soymilks, as well as many meat alternatives.
The benefits of soy go beyond its adaptability in dishes and different options for purchase at the store. Soybeans deliver about 14 grams of protein per a ½ cup cooked serving, which is more than a hot dog or glass of milk. Soybeans are a good source of iron, fiber, potassium and folate. Soy can also help lower cholesterol and may improve bone-mineral density as well as reduce the severity of hot flashes in women.
The link between soy and estrogen is due to soy‘s reputation as an “Isoflavone” powerhouse. Isoflavones are plant compounds that can mimic the behavior of estrogen in our bodies by binding to the same receptors, although many times soy has weak estrogen-like effects. Some new studies show that consuming soy foods after a breast cancer diagnosis improves prognosis and females who consume soy long-term from a young age could have a lower risk of breast cancer. Similarly, there is no evidence that soy foods have any effect on estrogen or testosterone levels in men.
So, why have so many spread the word that soy is “bad” for you? Besides possibly stemming from omnivore-based advocate groups, conclusions from select studies have been misinterpreted and falsely presented to the public as fact. Studies that have suggested negative effects of soy have been limiting in evidence or done on a small scale and much of these ideas are now being disproved.
Nutrition professionals and many health authorities conclude that soy is a safe food and one we can all enjoy. A recommended intake for soy is between two to four servings daily, with up to three servings for breast cancer patients. It’s time to give soy the credit it deserves!
By Molly McBride, RD, LD
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Messina, V. (2009). “RD Resources for Professionals: Isoflavones”, Vegetarian Nutrition Dietetic Practice Group of the Academy of Nutrition and Dietetics. Retrieved from: http://vndpg.org/
Norris, J., & Messina, V. (2011) Vegan for Life. Cambrige, MA: Da Capo Press, 119-123, 205-216.
Sharer, E.C. (2012). “RD Resources for Professionals: Vegetarian/Vegan Myths”, Vegetarian Nutrition Dietetic Practice Group of the Academy of Nutrition and Dietetics. Retrieved from: http://vndpg.org/