Sources of tofu can include soyas, which is a type of legume that is native to East Asia. It is a popular ingredient in many Asian dishes and is also used to make tofu. Soyas are high in protein and contain essential amino acids, making them a healthy alternative to animal proteins. They are also a good source of calcium, iron, and other minerals. Additionally, soyas are low in fat and cholesterol, making them a great choice for those looking to reduce their intake of unhealthy fats.