when lactosentolerant occur

My father visited a doctor who diagnosed him as lactose intolerant. This surprised me because he is 50 years old and he never had symptoms of something like this. I cannot believe his doctor gave him appropriate diagnosis, because I was thinking lactose intolerance start as soon as person is born. Can you tell me could it be true, or doctor misdiagnosed him? I want to hear more about condition called lactose intolerance, when does it occur.

Definitely, that could be right diagnosis for your father, because many people may not experience symptoms until they are much older. It could be re-checked if diagnosis is not definitely true or if his doctor still doubt about his lactose intolerance. The most common tests used to measure the absorption of lactose in the digestive system are the lactose tolerance test. He could have also the hydrogen breath test, and the stool acidity test. These tests are performed on an outpatient basis at a hospital, clinic, or doctor's office, and this way he could be sure in diagnosis. The lactose tolerance test begins with the individual fasting before the test and then drinking a liquid that contains lactose. Several blood samples are taken over a 2-hour period to measure the person's blood glucose. This is indicating how well the body is able to digest lactose, and is person lactose intolerant as you father is suspected to be. A large lactose load may be dangerous for the very young, but nothing could happen to your father. However, I would recommend his doctor to have tests done to confirm his diagnosis of lactose intolerant patient