Smoking and Crohn's disease
Recent research has suggested that nicotine may have a positive result on people with ulcerative colitis, while it has detrimental effect on people with Crohn's disease. People who have smoked in the past or who are currently smoking are at a higher risk for developing Crohn's disease than people who have never smoked.
Patients with Crohn's disease who smoke are also at an increased risk for relapses, repeated surgeries, and for requiring immunosuppressive treatment. The cessation of smoking is highly recommended by physicians in order to prevent Crohn's flare-ups.
Children or others who are around secondhand smoke also have a higher risk of developing Crohn's disease.