Does diet cause CD?

 "Imbalances in dietary consumption of fatty acids, vegetables, and fruits are associated with risk for Crohn's disease in children" in Am Journal Gastroenterol (2007)
Conclusions:  "Our findings indicate that an imbalance in consumption of fatty acids, vegetables, and fruits is associated with increased risks for CD among Canadian children."

"Dietary patterns and risk for Crohn's disease in children" in Inflamm Bowel Dis (2008) Conclusions:   Four dietary patterns each were observed among both boys and girls. Pattern 1 in girls, characterized by meats, fatty foods, and desserts, was positively associated with CD (OR 4.7, 95% CI 1.6-14.2). Pattern 2, common to both boys and girls, was characterized by vegetables, fruits, olive oil, fish, grains, and nuts and was inversely associated with CD in both genders (girls: OR 0.3, 95% CI 0.1-0.9; boys: OR 0.2, 95% CI 0.1-0.5).

"Role of diet in the development of inflammatory bowel disease" in Inflamm Bowel Dis (2010)
Conclusions:  "There is currently insufficient evidence to support a direct relationship between diet and IBD. However, there is some evidence to suggest a proinflammatory effect from dietary components and obesity, either directly or via gastrointestinal bacteria. The apparent association between sugar intake and IBD, in the absence of a possible mechanism, may indicate that sugar intake is a surrogate marker for smoking, and not an independent risk factor alone. However, more rigorous research is required. The majority of studies to date have concentrated on individual foods or nutrients. Epidemiologic studies of diet and health are increasingly focusing on dietary patterns that may potentially provide a more meaningful picture of dietary exposure. The answer may lie within a genetically susceptible individual with “proinflammatory” eating habits. Future research may need to focus on aspects of the whole diet prior to development of the disease and establishing links between diet and the host microbiota."

"Lifestyle-related disease in Crohn’s disease: Relapse prevention by a semi-vegetarian diet" in World J Gastroenterol (2010)
"[W]e regard IBD as a lifestyle-related disease that is mediated by mainly a westernized diet"