Healthcare providers and researchers have a lot to learn about Crohn’s disease, including what exactly causes it and why it develops. Current research, though, suggests the condition is caused by an abnormal immune system reaction to viruses or bacteria in the digestive tract. In an attempt to destroy these germs, the immune system mistakenly attacks and destroys the body’s own digestive tissues, leading to inflammation and damage in different parts of the digestive tract. 

A number of potential risk factors for Crohn’s disease have been identified, including modifiable (you can affect) and non-modifiable (you cannot affect) ones.

Causes and Risk Factors

  • Age: this condition can develop at any age, but it’s most likely to first occur when a person is between 15 and 35 (or at least younger than 40)
  • Family history: certain genes may make a person more likely to develop Crohn’s disease, since researchers have found that about 1 in 5 people with Crohn’s disease have a family member who has it, too
  • Smoking: people who smoke are about twice as likely to have Crohn’s disease as people who don’t smoke; smokers are also more likely to have a more severe disease progression and an increased risk of surgery and other complications
  • Ethnicity: people of Caucasian descent tend to get Crohn’s disease most often, although all ethnicities can be affected; the rates of Crohn’s disease among Hispanic, Asian, and Black populations is increasing recently, particularly in the United States and United Kingdom
  • Location: people who live in industrialized countries and urban areas appear to be more at risk for developing Crohn’s disease, which suggests that environmental factors could be at play 


How do you develop Crohn’s disease?

It’s not clear why some people get Crohn’s disease and others don’t, but doctors and researchers believe a combination of factors, including genetics and environment, can lead to its development. For example, a person may be more likely to develop Crohn’s if they have a family member who also has it. 

What are the first signs of Crohn’s disease?

Usually, the first signs of Crohn’s disease include abdominal pain (especially right after eating), diarrhea, fever, and unexplained weight loss. Specific signs can depend on the type of Crohn’s disease a person has or how severe it is.

Is Crohn’s disease serious?

Crohn’s disease is not considered life-threatening directly, but it can be serious and increase the risk of complications or other health problems that may be fatal, like infections and colorectal cancer. But the condition is manageable with the right treatment. 

What are the Differences Between Crohn’s Disease and Ulcerative Colitis?

According to the Crohn’s and Colitis Foundation, Crohn’s disease can affect any part of the digestive tract, from the mouth to the anus. Crohn’s disease can also leave normal areas of healthy intestinal tissue in between areas of damaged and inflamed tissue. By contrast, ulcerative colitis affects only the colon (large intestine), specifically the colon’s innermost lining. Furthermore, ulcerative colitis also does not leave any areas of healthy tissue in between areas of damaged tissue.

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