Diets with high inflammatory potential are associated with an increased risk for Crohn disease but not of ulcerative colitis (UC), researchers reported in Gastroenterology.
The investigators analyzed data from the Nurses’ Health Study (121,700 female registered nurses aged 30 to 55 years), the Nurses’ Health Study II (116,429 female nurses aged 25 to 42 years), and the Health Professionals Follow-Up Study (51,529 male health professionals aged 40 to 75 years). A total of 166,903 women and 41,931 men were included and contributed to 4,949,938 person-years (PY) of follow-up.
Among the participants, researchers observed 328 cases of Crohn disease and 428 cases of UC, yielding a crude incidence rate of 6.6/100,000 PYs and 8.6/100,000 PYs, respectively. The median age of inflammatory bowel disease (IBD) diagnosis was 55 (range, 29-85) years. The study authors calculated empirical dietary inflammatory pattern (EDIP) scores according to weighted sums of 18 food groups obtained from food frequency questionnaires.
Compared with participants in the lowest quartile of cumulative average EDIP score, the researchers found that participants in the highest quartile (highest dietary inflammatory potential) had a 51% higher risk for Crohn disease (hazard ratio [HR] 1.51; 95% CI, 1.1-2.07; Ptrend =.01). Compared with participants who had persistently low EDIP scores (at 2 time points, separated by 8 years), participants who shifted from a low to high inflammatory potential of diet or persistently consumed a pro-inflammatory diet had a greater risk for Crohn disease (HR 2.05; 95% CI, 1.1-3.79 and HR 1.77; 95% CI, 1.1-2.84, respectively). Dietary inflammatory potential was not associated with risk for ulcerative colitis (Ptrend =.62).
“The effect with Crohn’s disease was dynamic, where a shift from low to high inflammatory potential of diet and a persistently pro-inflammatory diet were both associated with greater disease risk,” stated the researchers.
Among several study limitations, the authors noted that self-reported dietary and lifestyle data are subject to measurement error, and the median age of IBD diagnosis is higher than that in other population-based cohorts.
“We demonstrate that consumption of diets with high inflammatory potential is associated with an increased risk of developing Crohn’s disease,” the investigators concluded. “Our findings support the importance of diet in modulating intestinal inflammation and IBD risk. Strategies to mitigate chronic inflammation through avoidance or reduced intake of pro-inflammatory foods may be considered for disease prevention.”
Lo C-H, Lochhead P, Khalili H, et al. Dietary inflammatory potential and risk of Crohn’s disease and ulcerative colitis. Gastroenterology. 2020;159(3):873-883.e1.