Medical questions & health advice by board certified doctors

"Can you slowly become lactose intolerant?"

ZocdocAnswersCan you slowly become lactose intolerant?


Over the years I just think that milk and cheese makes me feel worse and worse when I have them. Like I eat cereal every morning but more and more I think it makes my stomach hurt. Can you develop lactose intolerance over a long period of time??


Lactose intolerance is a result of a lactase deficiency leading to the inability to digest and metabolize lactose, a sugar found in milk and diary products. Sugar molecules cannot be absorbed through the wall of the small intestine into a bloodstream without the presence of the enzyme lactase to break them down. For this reason, when you drink milk or ingest diary products its lactose remains undigested and passes intact into the colon where enteric bacteria quickly take over to lactose metabolism producing significant amounts of gas (a mixture of hydrogen, carbon dioxide and methane) during fermentation that cause you abdominal pain, bloating, nausea, and acid reflux. The unabsorbed sugars and fermentation products also raise the osmotic pressure of the colon to give you diarrhea due to an increased flow of water into the bowels. Symptoms often occur 30 minutes to 2 hours after you eat or drink milk products. Lactose intolerance may be either genetic or environmentally induced. If left untreated, the symptoms of a lactose intolerance get worse, or you may develop new symptoms. Or, it can develop slowly and the symptoms may be confusing with other digestive conditions. On the other hand, there are other intestinal problems, such as irritable bowel syndrome, that may cause the same symptoms as lactose intolerance. I would suggest a visit with a primary care physician who can order enteroscopy, lactose-hydrogen breath test, lactose tolerance test, and stool pH to help diagnose whether or not your condition is a lactose intolerance.

Need more info?

See a doctor today


Find doctors by city
Find doctors by specialty
Find doctors by popular insurances