Inflammatory bowel disease (IBD) is a chronic, progressive immune-mediated inflammatory condition of the gastrointestinal tract. Environmental risk factors play a role in developing either type of IBD, Crohn's disease and ulcerative colitis; although the exact mechanism is still unknown. Herein, we review environmental risks from early life exposures, lifestyle and hygiene, vaccinations, surgeries, exposure to drugs and gastrointestinal pathogens that may increase the risk of developing IBD.