Drinking milk and cola together is likely to lead to diarrhea. Milk belongs to dairy products, the main components are protein and calcium, cola belongs to a carbonated beverage, there are acidic substances, if the milk and cola drink together, the bicarbonate in cola, will make the milk calcium ions agglutination, difficult to digest and absorb, and turn into calcium carbonate substances, serious cases may also lead to indigestion or diarrhea and other symptoms. And in this case the carbonic acid contained in the cola and other substances will make the milk protein denaturation, casein precipitates, while drinking may appear layered precipitation phenomenon, not only will reduce the nutritional value of drinking milk, but also increase the difficulty of gastrointestinal digestion, may lead to diarrhea. So it is not recommended to drink milk and cola together, if there is diarrhea, it is recommended to go to the hospital as soon as possible to seek medical treatment.