One and a half year old babies can drink pure milk, but it is prohibited if there is an allergic reaction. There are some nutrients in milk that are different from the composition and proportion of breast milk, but they contain most of the proteins, fats and other nutrients that babies need. In addition, one and a half year old babies have begun to add complementary foods, gastrointestinal function has been gradually perfected, therefore, can be appropriate to drink milk to supplement the body nutrients, but it is recommended that a small amount of food is appropriate, and can not be used as a complete replacement for breast milk and / or formula. If the baby’s digestive function is not good or milk allergy, it is recommended to consult a doctor in time, under the guidance of the doctor, to choose the appropriate formula, or to develop a reasonable regimen.