The dangers of adding complementary foods too early include increased incidence of allergic diseases, indigestion or increased risk of obesity in the long term. 1. Increased incidence of allergic diseases: premature addition of complementary foods, especially the allergens in some complementary foods, such as soy, egg white, seafood, nuts, etc., the allergic substances can lead to the child’s allergic constitution, the later allergic asthma, allergic conjunctivitis, allergic rhinitis, allergic enteritis and other incidence of increased, thus affecting the healthy growth of children. 2. Indigestion: the child’s digestive function is not well developed, some of the food in the anti-nutrients, such as anticoagulant, trypsin inhibitors, saponins, etc. can lead to abdominal pain, diarrhea, nausea, vomiting and other symptoms, which is not conducive to the health of the child’s gastrointestinal tract. 3. Lead to obesity: too early to add complementary foods will make the child protein, fat, carbohydrates and other nutrient ratios are imbalanced, some children are prone to excessive intake of food, the risk of obesity increased in the long term. Dietary guidelines recommend that children add complementary foods after six months to ensure the healthy growth of children.