I usually drink milk with cereal and every now and then a glass but lately my stomach has hurt when i drink milk. what could cause this?

Lactose intolerance: You may be having difficulty digesting the sugar found in milk and dairy products.

Lactose intolerance: If you also get gas, bloating and/or diarrhea this is a very likely reason. One way to check is to try Lactaid or Lactose reduced milk. If the problem is solved, then it is an intolerance to Lactose, a milk sugar, and you might have or develop the same problem with cheese, cottage cheese, cream cheese, and sadly, ice cream. However, you might do fine with yogurts and even frozen yogurt!

Lactose intolerance: Many people lose the ability to digest lactose (a milk sugar) as they get older. Even people with this problem are okay with a small amount of milk in their cereal or coffee but can't handle a glass of milk without bloating, gas, and diarrhea. Also people who are lactose intolerant can eat usually eat aged cheddar and swiss cheeses because the bacteria used to make them got rid of the lactose.

Lactose intolerance: In some people as they grow older the ability to digest milk decreases and that could cause abdominal pain, bloating and gas production, try to drink lactate free milk instead.