The TABACROHN Study Group conducted a multicenter prospective cohort study, demonstrating that smoking cessation improved the prognosis of Crohn's disease. Patients who continued to smoke were 50% more likely to relapse compared with non-smokers. Smoking cessation reduced the risk of fl aring, regardless of exposure to anti-tumor necrosis factor agents. Despite the evidence that smoking cessation is benefi cial, many patients do not quit smoking after their diagnosis of Crohn's disease. Lack of awareness, physical addiction, and social context of smoking inhibit smoking cessation. In spite of this, comprehensive smoking cessation programs have been shown to be effective and reduce costs.