Drinking milk in the morning on an empty stomach has many disadvantages, because it is an empty stomach, drink in the milk can not be fully enzyme digestion, will soon be nutrients in the protein into energy consumption, nutrients can not be well digested and absorbed. Some people may also appear as a result of abdominal pain, diarrhea, this is because their body generates less or very little lactase, drinking a lot of milk on an empty stomach, milk lactose can not be digested in a timely manner, by the bacterial decomposition of the intestinal tract and produce a large amount of gas, acid, stimulate intestinal contractions, abdominal pain, diarrhea. Therefore, it is best to eat something before drinking milk, or eat food while drinking milk, to reduce the lactose concentration, conducive to the absorption of nutrients.