What causes irritable bowel syndrome?
The exact cause of IBD is not known. One possible cause is a malfunction of the immune system. Heredity seems to be a contributing factor, as it is more common among people with a family history of the disease.
Other common risk factors include:
Age: Most people affected are diagnosed before the age of 30. However, some people don't develop the disease until their 50s or 60s.
Family history: If you have a close relative with the disease, such as a parent or sibling, you are at higher risk of developing the condition.
Smoking cigarettes: Smoking is the most important controllable risk factor for developing Crohn's disease. Smoking cigarettes may actually help to prevent ulcerative colitis, but its overall harm to your health greatly outweighs any benefit. Plus, quitting smoking can improve the general health of your digestive tract among other benefits.
Race or ethnicity: While it can occur in any race, it is more common among white people.
Nonsteroidal anti-inflammatory medications: Taking medications such as ibuprofen (Advil, Motrin IB, etc.), naproxen sodium (Aleve), diclofenac sodium, and others may increase the risk of developing IBD and can worse the disease in people already affected by it.