Dietary Patterns and Risk of Inflammatory Bowel Disease in Europe

TLDR

Nutrient associations with ulcerative colitis and Crohn's disease are inconsistent, and further research is needed to explore potential microbiota or other mechanisms. The study examined how overall dietary patterns relate to ulcerative colitis and Crohn's disease risk. Using a nested case–control design within EPIC, researchers assessed baseline dietary intake via food frequency questionnaires and calculated incidence rate ratios for UC and CD across Mediterranean diet quintiles and factor‑derived patterns. Overall, no dietary pattern predicted UC or CD risk, but after excluding early cases, a high‑sugar/soft‑drink pattern—especially when combined with low vegetable intake—was linked to increased ulcerative colitis risk.

Abstract

Specific nutrients or foods have been inconsistently associated with ulcerative colitis (UC) or Crohn's disease (CD) risks. Thus, we investigated associations between diet as a whole, as dietary patterns, and UC and CD risks. Within the prospective EPIC (European Prospective Investigation into Cancer) study, we set up a nested matched case–control study among 366,351 participants with inflammatory bowel disease data, including 256 incident cases of UC and 117 of CD, and 4 matched controls per case. Dietary intake was recorded at baseline from validated food frequency questionnaires. Incidence rate ratios of developing UC and CD were calculated for quintiles of the Mediterranean diet score and a posteriori dietary patterns produced by factor analysis. No dietary pattern was associated with either UC or CD risks. However, when excluding cases occurring within the first 2 years after dietary assessment, there was a positive association between a "high sugar and soft drinks" pattern and UC risk (incidence rate ratios for the fifth versus first quintile, 1.68 [1.00–2.82]; Ptrend = 0.02). When considering the foods most associated with the pattern, high consumers of sugar and soft drinks were at higher UC risk only if they had low vegetables intakes. A diet imbalance with high consumption of sugar and soft drinks and low consumption of vegetables was associated with UC risk. Further studies are needed to investigate whether microbiota alterations or other mechanisms mediate this association.