The exact incidence of Crohn’s is difficult to determine, as there is evidence that many people with the condition remain undiagnosed. Some estimates indicate that it may occur in one to 10 people per 100,000, but the exact number may be even higher.

The incidence of Crohn’s seems to be higher in North American and European populations than in Asian and African populations.

It is not known whether these differences actually represent racial differences or are due to socioeconomic or other factors such as better diagnosis. Crohn’s disease affects males and females in equal numbers.

Most people get Crohn’s disease between 15 and 40 years of age with it being more likely to first occur when you are a teenager or in your 20s.

However, children can sometimes develop Crohn’s disease, as can people in later life, such as in their 60s and 70s.

Though it is unclear why, the growth spurt of puberty seems to be a common time when Crohn’s disease first manifests itself.

There is some component of Crohn’s disease that is genetic, as it seems to run in families. You are more likely to get it if you have a family member who has either Crohn’s or ulcerative colitis.

Having a sibling or parent with Crohn’s is the greatest risk factor for disease and there is a ten-fold increased risk of getting it.

Researchers have found that a change or mutation in one gene increases your risk and it is believed that this gene may play a role in how we fight off infection. However, only one in five of those with Crohn’s have this gene so it is only one possible cause of the disease.