Association of Dietary Components and Combined Dietary Profiles with Ulcerative Colitis: A Case-Control Study

Background and Objectives: Diet is a potential modifiable risk factor for ulcerative colitis (UC). This study examined the associations of individual dietary components and combined dietary profiles with UC. Methods and Study Design: This case-control study included 157 patients with UC and 395 controls. Dietary consumption frequencies were converted into ordinal scores ranging from 1 to 4. Participants were additionally classified into four dietary profiles based on combined levels of risk-promoting and protective food consumption. Logistic regression models were used to estimate odds ratios (ORs) and 95% confidence intervals (CIs). Results: Higher consumption of fast food (OR = 5.30, 95% CI: 3.65, 7.70), carbonated soft drinks (OR = 9.37, 95% CI: 5.78, 15.18), and spicy food (OR = 1.56, 95% CI: 1.21, 2.01) was positively associated with UC. Dairy consumption was inversely associated with UC (OR = 0.52, 95% CI: 0.33, 0.82). In sex-stratified analyses, vegetable consumption was inversely associated with UC among women only. Compared with participants with high risk-promoting/low protective food consumption, those with low risk-promoting/low protective food consumption (OR = 0.07, 95% CI: 0.02, 0.21) and those with low risk-promoting/high protective food consumption (OR = 0.08, 95% CI: 0.03, 0.17) had substantially lower odds of UC. The high risk-promoting/high protective food consumption was not associated with UC. Conclusions: Frequent consumption of fast food, carbonated soft drinks, and spicy food was associated with higher odds of UC, whereas dairy consumption was associated with lower odds. Lower consumption of risk-promoting foods, irrespective of protective food consumption, was associated with substantially lower odds of UC. Prospective studies are needed to confirm these associations.