Food Allergies & Intolerance
Diagnosing Lactose Intolerance
Is it possible to become lactose intolerant at a later age? What should you do about lactose intolerance?
According to the experts at Mayo Clinic, lactose intolerance can develop any age. It might be triggered by another medical condition like Crohn’s disease, or there may be another cause. Dr. Rohit Divekar, Allergic Diseases, Mayo, suggests an evaluation by your health care practitioner to make sure the condition you have is lactose intolerance.
Lactose intolerance, Mayo says, results from a problem with the carbohydrate lactose, a type of sugar found in dairy products. When you eat or drink dairy products, enzymes in your small intestine digest lactose so the body can make energy. But in people with lactose intolerance, an enzyme called lactase is not present. That means that the body cannot break down the lactose. As a result, sugar ferments in the intestines, leading to symptoms such as diarrhea, nausea, abdominal cramps, bloating and gas.
Sometimes, Divekar says, lactose intolerance develops when the small intestine’s production of lactase decreases after an illness, injury or surgery involving the small intestine. That condition is known as secondary lactose intolerance. This kind of lactose intolerance has been linked to celiac disease and Crohn’s disease. The lactose intolerance may be reversed if a doctor treats the underlying disorder.
With primary lactose intolerance, Divekar says, people who develop primary lactose intolerance start life making normal levels of lactase — a necessity for infants, who get all their nutrition from milk. As children replace milk with other foods, lactase production normally decreases. It stays high enough, though, to digest the amount of dairy in a typical adult diet. In primary lactose intolerance, lactase production declines below normal at some point for reasons that are unclear. The low amount of lactase then makes milk products difficult to digest and leads to lactose intolerance symptoms.
There’s a lactose intolerance test to confirm a diagnosis of the illness. The patient consumes a drink containing lactose, and a blood sample is taken to measure glucose levels. If the patient’s glucose level doesn’t rise, that means the body isn’t properly digesting and absorbing lactose.
Alternatively, another there’s a hydrogen breath test. . This test also requires you to consume a drink that contains high levels of lactose. Your doctor next measures the amount of hydrogen in your breath. Normally, very little hydrogen is detectable. Larger-than-normal amounts of hydrogen measured during this test are a sign that your body isn’t fully digesting and absorbing lactose. (If the result of the procedure doesn’t indicate lactose intolerance, Mayo says, your doctor may see whether other digestive conditions are causing your symptoms.)