The soybean itself is a notably inauspicious staple food; it contains a whole assortment of "antinutrients" - compounds that actually block the body's absorption of vitamins and minerals, interfere with the hormonal system, and prevent the body from breaking down the proteins of the soy itself.
In Defense of Food: An Eater's Manifesto (ed. Penguin, 2008) - ISBN: 9781101147382