Diseases That Could Suddenly Make You Lactose Intolerant

You or someone you know probably has lactose intolerance. People who are lactose intolerant will feel abdominal cramps, bloating, or gas 30 minutes to two hours after consuming lactose-containing dairy because their bodies don't produce enough lactase enzyme to digest the sugar (lactose) in milk. According to Boston Children's Hospital, 15% of Americans are lactose intolerant, and the condition is much more common in people with African American, Asian American, and Native American heritages.

Most people with lactose intolerance will develop the condition after childhood as people drink less milk. Your body produces enough of the lactase enzyme in infancy to digest lactose, but this lactase production declines as you get older (via Mayo Clinic). In rare cases, some infants are born with a gene variant that causes them to produce insufficient lactase. However, some diseases, such as Crohn's disease and celiac disease, can affect the production of lactase in your system. Intestinal infections and bacterial overgrowth could also make you lactose intolerant.

Secondary lactase deficiency

According to the American College of Gastroenterology, secondary lactase deficiency occurs as a symptom of another condition, such as celiac disease. People who can't consume foods with gluten, such as wheat, rye, or barley, can also develop lactose intolerance. Your lactose intolerance could also accompany Crohn's disease, which is an inflammatory disease of the gastrointestinal tract.

Children might develop lactose intolerance if they get an infection from an organism such as a rotavirus. Rotaviruses can cause vomiting, diarrhea, and fever, as well as temporary lactose intolerance as they damage the lining of the small intestine. The giardia parasite is typically found in contaminated lakes, swimming pools, and hot tubs (via the Centers for Disease Control and Prevention), and you can become infected if you accidentally swallow the water. It will sit in your intestines and cause diarrhea, stomach cramps, and dehydration. Giardia can also cause lactose intolerance. If your lactose intolerance stems from a disease or infection, it will resolve as you treat the primary condition.

Treating lactose intolerance

If you suspect you might be lactose intolerant, your healthcare provider has a few tests to confirm the condition. A hydrogen breath test can measure the gases produced by the bacteria in your gut. A blood sugar test or stool acidity test can also determine whether your body absorbs lactose (via Cleveland Clinic).

Whether your lactose intolerance is temporary or permanent, reducing or removing foods and drinks with lactose will resolve uncomfortable symptoms. Because people with lactose intolerance lack the digestive enzyme lactase, lactase tablets and drops are available to help digest dairy products (via the National Institutes of Health). There are also dairy-free options and dairy products that have lactose removed or reduced.

Rather than rely on dairy products for your calcium needs, you can load up your plate with green vegetables like broccoli and kale to get your daily calcium. Salmon and sardines are also good sources of calcium. Having lactose intolerance doesn't necessarily mean giving up dairy altogether. The active cultures in yogurt also have lactase to help you digest this food to get your daily calcium (via Boston's Children's Hospital).