The soybean contains large quantities of natural toxins or “antinutrients.”

http://www.mercola.com/article/soy/avoid_soy.htm

http://www.westonaprice.org/health-topics/whey-to-go-soy-protein-lowers-testosterone-in-strength-training-men/

http://drelaine.com/why-men-should-avoid-soy/

http://www.tandfonline.com/doi/abs/10.1080/07315724.2013.770648#.VCJAD5SSxd8