Moderate consumption of soy foods is unlikely to have adverse effects in adults; it may even benefit cardiovascular health and reduce cancer risk. Eating large amounts of soy foods for 6 months or more, however, may cause problems. Also, the use of soy infant formulas should probably be minimized.
— Read on examine.com/nutrition/is-soy-good-or-bad/
Pretty exhaustive review of the health effects of soy. BOTTOM LINE: soy is great for you (unless of course you are allergic). Just keep it non GMO and organic if possible (remember these are not the same – see my website for an explanation)