Dietary intake of vegetables, fruit, and antioxidants and risk of ulcerative colitis: a case-control study in Japan
Yoshihiro Miyake Nutrition Available online 2 June 2021, 111378
Highlight
• Intake of green and yellow vegetable was not related to ulcerative colitis.
• Intake of other vegetables was inversely related to ulcerative colitis.
• Vitamin C intake was inversely related to ulcerative colitis.
• Retinol intake was inversely related to ulcerative colitis.
Objective: Oxidative stress is considered to be one of the etiologic factors involved in ulcerative colitis (UC), yet there is limited epidemiological information regarding the relationship between antioxidant intake and the risk of UC. The aim of the present case–control study in Japan was to examine the association between intake of green and yellow vegetables, other vegetables, fruit, vitamin C, vitamin E, retinol, α-carotene, β-carotene, and cryptoxanthin and UC risk.
Methods: Included were 384 cases within three years of diagnosis with UC and 665 controls. Data on dietary intake and confounders were obtained using a self-reported questionnaire. Information on dietary factors was collected using a 169-item semi-quantitative food-frequency questionnaire. Adjustment was made for sex, age, pack-years of smoking, alcohol consumption, history of appendicitis, family history of UC, education level, and body mass index.
Results: Higher intake levels of other vegetables, vitamin C, and retinol were independently associated with a reduced risk of UC: the adjusted odds ratio between extreme quartiles was 0.51 (95% confidence interval [CI]: 0.34−0.76, P for trend = < 0.001) for other vegetables, 0.45 (95% CI: 0.30−0.69, P for trend = < 0.001) for vitamin C, and 0.64 (95% CI: 0.43−0.95, P for trend = 0.04) for retinol. There were no associations between intake of green and yellow vegetables, fruit, vitamin E, α-carotene, β-carotene, or cryptoxanthin and UC risk (P for trend = 0.29, 0.56, 0.89, 0.20, 0.69, and 0.22, respectively).
Conclusions: Intake of other vegetables, vitamin C, and retinol was inversely associated with UC risk.