Although many soyfoods are rich in iron, the iron may not be very well absorbed by the body. Also, the iron in soy-meat blends appears to be well absorbed. Calcium is another nutritional characteristic of soy. One-half cup of soybeans contains almost 90 milligrams of calcium, which is about 10 percent of the RDA for this nutrient. Roasted soynuts, textured soy protein and tempeh are also good calcium sources.
Processing increases the calcium content of some soyfoods.
For example, some tofu is made using a calcium salt, making this type of tofu rich in calcium. Soymilk is sometimes fortified with calcium. In addition to being nutritious, soyfoods may play a role in disease prevention. Soybeans and the foods made from them are rich in special compounds called isoflavones. Soyfoods are the only foods that contain significant amounts of these compounds.