Smoking, breastfeeding, physical inactivity, contact with animals, and size of the family influence the risk of inflammatory bowel disease: A Slovak case–control study

The aetiology of inflammatory bowel disease (IBD) is not known but is likely to involve a combination of genetic predisposition and environmental risk factors. Smoking has been associated consistently with a higher risk of Crohn's disease (CD), while appendectomy and smoking appear to diminish the risk of ulcerative colitis (UC). The roles of other environmental factors are unclear. The aim of the present study was to evaluate the association of...