The exact causes of inflammatory bowel disease (IBD) are difficult to prove, but there are some recognized risk factors which we've listed below based on information from health.com: People who live in developed western countries, like are more likely to have inflammatory bowel disease. This could be down to lifestyle choices such as smoking, drinking, a diet of processed foods, or the effects of pollution. However, less-developed countries, particularly in Asia, are experiencing a rise in the number of cases of IBD. This could also be due to the increase of processed foods in worldwide diets or an increase in environmental pollution. Find out about Thalia's journey with Crohn's disease.