Lactose is a type of sugar found in milk and other dairy products. An enzyme called lactase is made in the small intestine to help break down this sugar so milk and dairy products can be digested.
If a person doesn’t have enough lactase in their body, they are lactose intolerant. This means their bodies can’t absorb lactose. This can cause abdominal bloating and cramps, gas, diarrhea and nausea.
In adults, lactose intolerance is very common and not dangerous. Lactose intolerance can prevent an infant from properly digesting milk, including breast milk. Premature babies are born with lactose intolerance.
There is no way to prevent lactose intolerance. Decreasing or removing milk products from the diet usually improves the symptoms. Certain dairy products are easier to digest, such a yogurt, buttermilk and cheeses. Lactose-free products can be substituted for traditional milk products for adults and older children.