Soy has been a major staple in Asian cultures for centuries, and their incidence of coronary artery disease, hypertension, ischemic stroke, hormone-dependent cancers, osteoporosis, postmenopausal hip fracture, diabetes, and obesity are all markedly lower than what is in the Western world.
Soy contains a form of plant estrogen called isoflavones, but these phytochemicals aren’t the same thing as human estrogen. They’re natural, nonsteroidal compounds sometimes called phytoestrogens, which are also found in flax seeds, sesame seeds, garlic, peanuts, beer, and more.
Even though soy isoflavones have properties similar to human estrogen, evidence suggests that they actually have beneficial anti-estrogenic effects in breast tissue, while also having beneficial estrogen-mimicking effects in bone tissue.
Soy cultivation is a major driver of deforestation in the Amazon basin. Seeds from the soybean plant provide high protein animal feed for livestock, and 80% of Amazon soy is destined for animal feed; smaller percentages are used for oil or eaten directly. Today Brazil has 24-25 million hectares devoted to the growth of this crop, and is currently the second largest producer of soybeans in the world.