To answer this question, it’s important to understand where much of the soy panic comes from in the first place. Research has shown that soy contains estrogen-like compounds called isoflavones (genistein and daidzein are the specific names), which were once believed to interfere with hormones cause breast cancer , and contribute to thyroid issues. For these reasons, many people have been scared of soy. But in truth, the soy you eat doesn’t contain enough isoflavones to have an impact on your health, and soy’s effect on the body is far more complex than this early research indicated. So, unless you have a soy allergy, there's really no reason to fear soy, says Taylor Wolfram , MS, RD, CDN, a registered dietitian in Chicago.