Crohn’s disease is a chronic inflammatory bowel disease (IBD) characterized by inflammation of the intestine. If left untreated, it can cause serious illness or disability. The symptoms of Crohn’s disease are sometimes mistaken for those of lactose intolerance, a condition that’s less serious but much more common.

Lactose intolerance is caused by a person’s inability to produce enough, or any, of the enzyme lactase. This enzyme is typically found in the small intestine and digests lactose, a sugar found in dairy products. Lactose intolerance, also known as lactase deficiency, causes digestive discomfort in people who are sensitive to lactose. Symptoms include diarrhea, bloating, and gas, some of the same symptoms associated with Crohn’s disease.

Since these two conditions share many of the same symptoms, it’s possible to think you have one when you really have the other. Complicating matters is the fact that people with Crohn’s disease are more likely to have lactose intolerance than the general population.

Cramping and persistent diarrhea usually accompany both Crohn’s disease and lactose intolerance. However, a person with Crohn’s may also find blood or mucus in the stool.

Other symptoms of Crohn’s that aren’t typically found in people with lactose intolerance are:

Crohn’s disease may go into remission for weeks or months at a time with few or no symptoms. A person with lactose intolerance will experience symptoms every time they consume dairy products.

There are multiple risk factors for Crohn’s disease. They include:

Age

The Mayo Clinic states that Crohn’s disease is most likely to develop in people who are under 30 years old, although it can occur at any age.

Ethnicity

Crohn’s is more common in Jewish people of Eastern European, or Ashkenazi, descent than in non-Jewish Europeans. Overall, Caucasians are more likely to have Crohn’s than black people. However, according to the Mayo Clinic, Crohn’s disease rates are increasing among black people in North America and the United Kingdom.

Lactose intolerance occurs in almost all people of Asian and Native American descent. It’s common among individuals with South Indian, African, and Ashkenazi Jewish ancestry as well.

In addition, some people begin to lose a portion of their lactase enzymes as they age. This makes them less able to digest foods containing lactose.

Several studies also indicate that lactose intolerance is more common in those with Crohn’s disease than in those without it. Despite these findings, a diagnosis of Crohn’s disease doesn’t mean you’ll definitely develop lactose intolerance.

It’s important to note that lactose intolerance isn’t a type of food allergy and it isn’t harmful, even for people with Crohn’s disease. However, it may add to a person’s discomfort.

Most people with lactose intolerance can digest at least some lactose, but how much depends on the amount of lactase in their bodies. For some, the lactase enzyme may be inducible. This means that if a person regularly exceeds the amount of lactose they can normally tolerate, their body may respond by increasing the amount of lactase it produces.

Crohn’s disease causes inflammation in various areas of the digestive tract. Its symptoms can range from mild to severe. At the moment, there’s no cure for this condition. However, its symptoms can typically be managed effectively.

Symptoms of Crohn’s disease can include:

If Crohn’s is left untreated, additional symptoms may occur. These include:

  • inflammation of the joints
  • inflammation of the eyes and skin
  • inflammation in the liver and bile ducts
  • delayed puberty, or growth, in children

When a person without lactose intolerance eats lactose, the enzyme lactase breaks it down into a pair of simpler sugars. Both of these sugars, glucose and galactose, absorb quickly through the small intestine and release into the bloodstream.

However, if someone doesn’t have enough lactase, the small intestine can only digest a portion of the lactose. As the undigested lactose travels through the small intestine and into the colon, it draws in water through osmosis. This excess water is responsible for the cramps and diarrhea sometimes associated with lactose intolerance.

Other symptoms of the condition include:

These symptoms occur during the fermentation process, which happens when bacteria in the colon work to break down lactose. As the bacteria act on the lactose, it turns into an acid, which then produces gas.

In addition to the other symptoms, the acid may also cause anal burning.

There’s no one specific test that can diagnose Crohn’s. Your doctor may perform a variety of tests in order to rule out other potential causes of your symptoms.

Several tests are used to pinpoint the disease, and may include:

  • Blood tests. Blood tests may be used to rule out underlying infections or anemia.
  • Fecal occult blood test. This test is used to check for hidden blood in the stool.
  • CT scan. A CT scan will allow your doctor to view the small intestine.
  • MRI. An MRI will allow your doctor to look for fistulas, or openings, in the small intestine.
  • Esophagogastroduodenoscopy. This procedure allows your doctor to view the food pipe, stomach, and small intestine with the help of a small camera. It can be done with or without biopsy.
  • Colonoscopy. A colonoscopy may be performed to search for inflammatory cells known as granulomas. It can occur with or without biopsy.
  • Balloon-assisted enteroscopy. An enteroscopy allows your doctor to look deeply into the small intestine. This test is often used to confirm a diagnosis.

The easiest way to diagnose lactose intolerance is to avoid dairy products such as milk, cheese, and ice cream and see if the symptoms go away. If, after one week, you consume a glass of milk and the cramps and diarrhea return, it’s highly likely that you are lactose intolerant.

Another more objective way to test for lactose intolerance is to have a doctor order a lactose breath test. When lactose metabolizes in the colon as opposed to the small intestine like it should, the bacteria will release hydrogen into the bloodstream. This hydrogen can then be measured in the breath. People who are lactose intolerant will have higher amounts of hydrogen in their breath.

The treatments for Crohn’s disease center on reducing inflammation and eliminating complications that might arise over time. While there’s currently no cure for this condition, long-term remission is possible. The effectiveness of treatments can vary from person to person. Treatments include:

Lifestyle changes can also positively affect both quality of life and the effectiveness of medical treatments. The most important thing you can do is to stop smoking cigarettes or using any other form of nicotine or tobacco. Identifying your food triggers, such as dairy or fiber, will also help.

People with Crohn’s disease may also experience more symptoms of lactose intolerance when they consume high-fat dairy products as opposed to those that are lower in fat. Experimenting with eating different types of foods can help you identify your specific triggers.

Currently, there are only two ways to treat lactose intolerance. You can avoid dairy products completely, or you can consume additional lactase enzymes in the form of an over-the-counter supplement (OTC) such as Lactaid. Additionally, people who give up dairy may need to supplement their diets with vitamin D and calcium tablets. You can also supplement your diet with nondairy sources of both vitamin D and calcium.

Most vitamin D is acquired through sun exposure. Foods that naturally contain this nutrient include egg yolks and liver. Many other foods are also enriched with vitamin D, including milk and some breakfast cereals.

Nondairy sources of calcium include:

Shop for lactase enzymes such as Lactaid. Also shop for vitamin D supplements and calcium supplements.

Since they both affect the digestive tract, Crohn’s disease and lactose intolerance share many of the same symptoms. It’s important to pinpoint which condition you have, because Crohn’s disease is serious and can become dangerous if left untreated. Your doctor will be able to help you determine which condition is causing your symptoms. They can also help you decide on the most appropriate treatment.

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