Soybeans are a member of the legume family, which include plant species that bear seed pods that split upon ripening. Some examples of other legumes include beans, peas, lentils and peanut. People with a soy allergy are not necessarily allergic to other legumes. If you are allergic to soy, you do not have a greater chance of being allergic to another legume (including peanut) than you would to any other food.