Symptoms lactose intolerance  can be mild or severe, depending on how much lactase your body makes. Symptoms usually begin 30 minutes to 2 hours after eating or drinking milk or milk products. If you have lactose intolerance, your symptoms may include:

  • Pain or cramps in the lower belly.
  • Bloating
  • Gurgling or rumbling sounds in the lower belly.
  • Gas.
  • Loose stools or diarrhea. Sometimes the stools are foamy.
  • Throwing up

Sometimes people who have never had problems with milk or dairy products suddenly have lactose intolerance. This is more common as you get older. Symptoms of the most common type of lactose intolerance-adult lactose intolerance-often start during the teen or adult years and continue for life. Symptoms of acquired lactose intolerance last as long as the small intestine does not make lactase.