Lactose intolerance is the answer. Lactose is a sugar found in milk products and it needs to be digested by our gastrointestinal tract with the help of enzyme lactase.
The percentage of the population that has a decrease in lactase as they age is less than 10% in Northern Europe and as high as 95% in parts of Asia and Africa.
Main symptoms of lactose intolerance are:
- abdominal pain
- bloating
- diarrhea, gas, nausea
Symptoms starts in 2,5h after drinking milk or eating any kind of food containing lactose.