Soy and soy-based foods contain phytoestrogens and their consumption at high levels in many countries has occurred for decades with no problems. When the possibility of the phytoestrogens in soy to reduce certain types of cancers and improve other health parameters was learned, this opened the door to specific foods and supplements to provide these substances. Data on the benefits is inconclusive and long-term safety of high dose supplemental phytoestrogens is not known for certain. However, high soy food-based diets have a long history of safety and certainly 1 or 2 servings/day would not be harmful (and possibly helpful) to a vast majority.