Soy gets a bad rap, people associate it with being a hippie and tree hugging, even though soy is a very healthy food, like edamame beans, but there is this silly notion that eating soy lowers testosterone and is bad for men. Not true. From his member center, Dr. Fuhrman talks about soy and manliness:
Question: My husband and I just started your plan, but recently my mother-in-law said that I was hurting my husband by making him eat more soy. She said that soy is not good for men because it contains phytoestrogens. Is what she is saying true? She cited an article in Men's Health that mentioned lower testosterone and sperm counts.
Dr. Fuhrman: Totally untrue, that is a biased, meat-promoting article written to bash soy. Men's magazines are not the place for reliable information about complicated health issues. If soy did lower testosterone it might be good because the high-meat American diet causes an excess of testosterone, leading to higher prostate cancer risk. Nevertheless this is not true anyway. See this study in the European Journal of Clinical Nutrition.
Flickr: John McNab