After consuming a milk based product, you will feel like having a diarrhea 20 to 30 minutes after you drink it. First you will experience a gurgling sound on your stomach, then it will be painful as cramps, and then a diarrhea will happen. It is hard for them to drink milk based products because the reaction is fast once it gets in the body. It happens when the bacteria in the colon ferment lactose once it enters the body. It is like getting rotten. It is always not good. You get the feeling of bloating, and sometimes constipation. Some of the symptoms are, mouth ulcer, fatigue, headaches and stress. You get stress when you are feeling you are about to poop and more stressful when you are in the street for sure. This is very common so reduce the intake of milk product.