It is currently recommended that babies at six months can be fed complementary foods. The appropriate age to start complementary feeding is when most children reach six months of age. The reasons for this are that babies at this age are interested in being fed and are able to hold their own food; they like to put things in their mouths; they have good control of their tongues to move food around in their mouths; and they begin to chew through the opening and closing of the upper and lower jaws. In addition, the early addition of complementary foods will reduce the intake of breast milk, which will reduce the protective factors in breast milk and increase the risk of disease. Babies with underdeveloped stomachs and intestines are susceptible to the risk of diarrhea. Babies cannot digest and absorb non-human proteins well, which increases the risk of allergic diseases. Therefore, it is recommended that babies start to add complementary foods after 6 months of age.