Peer Reviewed

inflammatory bowel disease

IBD Risk Is Increased With Ultra-Processed Food Consumption

A diet higher in ultra-processed food is associated with an increased risk of inflammatory bowel disease (IBD), according to the results of a recent study.1

“Inflammatory bowel disease (IBD) is more common in industrialized nations and it is thought that dietary factors might play a role, but data linking ultra-processed food intake with IBD are limited,” the authors wrote in a press release.2

In order to examine this relationship further, they conducted a prospective cohort study involving 116,087 adults aged 35 to 70 years from 21 low- middle-, and high-income counties across 7 geographical regions.

All participants were taking part in the Prospective Urban Rural Epidemiology study and had available food frequency questionnaire data. Outcomes of the study included the development of Crohn disease or ulcerative colitis.

During a median follow-up of 9.7 years, 467 cases of IBD were identified (90 Crohn disease and 377 ulcerative colitis). Overall, higher intake of ultra-processed food was associated with increased risk of IBD (hazard ratio 1.82, 95% CI 1.22 to 2.72 for ≥5 servings/day and 1.67, 1.18 to 2.37 for 1-4 servings/day compared with <1 serving/day, P=0.006 for trend). These rates did not differ significantly between Crohn disease and ulcerative colitis.

Various subgroups of ultra-processed foods, including soft drinks, refined sweetened foods, salty snacks, and processed meat were all associated with higher risk of IBD, while white meat, red meat, dairy, starch, fruit and vegetables, and legumes were not associated with increased risk.

“As white meat, unprocessed red meat, dairy, starch, and fruit, vegetables, and legumes were not found to be associated with development of IBD, this study suggests that it might not be the food itself that confers this risk but rather the way the food is processed or ultra-processed,” they wrote.1

“A possibility also remains of residual confounding owing to unmeasured or unknown confounders. Further studies are needed to identify specific potential contributory factors among processed foods that might be responsible for the observed associations in our study.”1

—Michael Potts


Narula N, Wong ECL, Dehghan M, et al. Association of ultra-processed food intake with risk of inflammatory bowel disease: prospective cohort study. BMJ. Published online July 15, 2021.

Ultra-processed food linked to higher risk of IBD. News release. BMJ; July 14, 2021. Accessed July 23, 2021.