title: Dietary risk factors for inflammatory bowel disease: a multicenter case-control study in Japan.
abstract: To evaluate the role of dietary factors in the etiology of inflammatory bowel disease (IBD), we conducted a multicenter hospital-based case-control study in a Japanese population. Cases were IBD patients aged 15 to 34 years [ulcerative colitis (UC) 111 patients; Crohn's disease (CD) 128 patients] within 3 years after diagnosis in 13 hospitals. One control subject was recruited for each case who was matched for sex, age, and hospital. A semiquantitative food frequency questionnaire was used to estimate preillness intakes of food groups and nutrients. All the available control subjects (n = 219) were pooled, and unconditional logistic models were applied to calculate odds ratios (ORs). In the food groups, a higher consumption of sweets was positively associated with UC risk [OR for the highest versus lowest quartile, 2.86; 95% confidence interval (CI), 1.24 to 6.57], whereas the consumption of sugars and sweeteners (OR, 2.12; 95% CI, 1.08 to 4.17), sweets (OR, 2.83; 95% CI, 1.38 to 5.83), fats and oils (OR, 2.64; 95% CI, 1.29 to 5.39), and fish and shellfish (OR, 2.41; 95% CI, 1.18-4.89) were positively associated with CD risk. In respect to nutrients, the intake of vitamin C (OR, 0.45; 95% CI, 0.21 to 0.99) was negatively related to UC risk, while the intake of total fat (OR, 2.86; 95% CI, 1.39 to 5.90), monounsaturated fatty acids (OR, 2.49; 95% CI, 1.23 to 5.03) and polyunsaturated fatty acids (OR, 2.31; 95% CI, 1.12 to 4.79), vitamin E (OR, 3.23; 95% CI, 1.45 to 7.17), and n-3 (OR, 3.24; 95% CI, 1.52 to 6.88) and n-6 fatty acids (OR, 2.57; 95% CI, 1.24 to 5.32) was positively associated with CD risk. Although this study suffers from the shortcoming of recall bias, which is inherent in most retrospective studies (prospective studies are warranted to confirm the associations between diet and IBD risk), the present findings suggest the importance of dietary factors for IBD prevention.
authors.affiliation: Department of Hygiene, Hyogo College of Medicine, Hyogo, Japan. naomasas@hyo-med.ac.jp
authors.forename: Naomasa
authors.initials: N
authors.lastname: Sakamoto
authors.forename: Suminori
authors.initials: S
authors.lastname: Kono
authors.forename: Kenji
authors.initials: K
authors.lastname: Wakai
authors.forename: Yoshihiro
authors.initials: Y
authors.lastname: Fukuda
authors.forename: Masamichi
authors.initials: M
authors.lastname: Satomi
authors.forename: Takashi
authors.initials: T
authors.lastname: Shimoyama
authors.forename: Yutaka
authors.initials: Y
authors.lastname: Inaba
authors.forename: Yoshihiro
authors.initials: Y
authors.lastname: Miyake
authors.forename: Satoshi
authors.initials: S
authors.lastname: Sasaki
authors.forename: Kazushi
authors.initials: K
authors.lastname: Okamoto
authors.forename: Gen
authors.initials: G
authors.lastname: Kobashi
authors.forename: Masakazu
authors.initials: M
authors.lastname: Washio
authors.forename: Tetsuji
authors.initials: T
authors.lastname: Yokoyama
authors.forename: Chigusa
authors.initials: C
authors.lastname: Date
authors.forename: Heizo
authors.initials: H
authors.lastname: Tanaka
mesh_terms: D000293:Adolescent; D000328:Adult; D001205:Ascorbic Acid / Q000494:pharmacology; D016022:Case-Control Studies; D003093:Colitis, Ulcerative / Q000209:etiology* / Q000517:prevention & control; D003424:Crohn Disease / Q000209:etiology* / Q000517:prevention & control; D004032:Diet; D004041:Dietary Fats; D019422:Dietary Sucrose; D005260:Female; D006801:Humans; D007564:Japan; D008297:Male; D011939:Mental Recall; D016017:Odds Ratio; D015203:Reproducibility of Results; D012307:Risk Factors; D017747:Seafood
chemical_list: D004041:Dietary Fats; D019422:Dietary Sucrose; D001205:Ascorbic Acid