People all around the world from different ethnicities and races are affected by Crohn’s disease and ulcerative colitis. The exact cause is still a mystery, but scientists have hit on some clues:
A faulty immune system: Scientists believe there could be a fault in the immune system that allows bacteria to invade the intestines and cause inflammation. The inflammation lasts longer than it would in a healthy person, because the immune system of someone with Crohn’s or colitis isn’t capable of flipping the inflammation switch.
Environmental factors: Smoking, diet (such as those high in refined sugars, animal proteins, and fats), certain drugs (such as non-steroidal anti-inflammatory drugs, or NSAIDs, like aspirin, Advil, and Aleve; oral contraceptive pills; and antibiotics), and stress are thought to change the function of the immune system or alter the population of intestinal bacteria and cause chronic inflammation in the intestines.
In addition, because of the improved hygiene conditions that we have today in the developed, children aren’t exposed to as many germs. So, the immune system has shifted away from fighting infection to developing autoimmune diseases like Crohn’s and colitis.
Genetics: Gene mutations are thought to be unique in Crohn’s and colitis patients and may be the culprit in causing defects in the immune system and other mechanisms, leading to persistent inflammation in the intestines. In addition, if you have a family history of Crohn’s and colitis, you’re more likely to have the disease yourself (especially if the family history is in a first-degree relative — parents, children, or siblings).
All these factors are just potential causes of Crohn’s and colitis. For example, plenty of people with a family history never develop the disease themselves, and plenty of people with the disease have no family history.