Significant associations do not exist between inflammatory potential of the diet and objective markers of disease activity in a cohort of patients with inflammatory bowel disease (IBD), according to a study.
“Among patients with IBD, pro-inflammatory dietary patterns and excess adiposity are highly prevalent,” the researchers said. “Despite greater central adiposity in patients in remission, no significant associations were found between Dietary Inflammatory Index with or without adjustment for energy density (E-DII or DII) scores and endoscopic and radiological markers of disease activity.”
Sixty-two patients with IBD participated in this observational, cross-sectional study, which sought to explore the association between endoscopic/radiological activity of IBD, body adiposity, and E-DII or DII. Endoscopic activity was defined as follows: an endoscopic Mayo score >2, Crohn’s Disease Endoscopic Index of Severity (CDEIS) >5, and/or the presence of a deep ulcer in any intestinal segment.
The researchers estimated body adiposity using BMI, waist circumference, and waist-hip ratio (WHR) and calculated DII and E-DII scores from a validated quantitative food frequency questionnaire. Based on the DII and E-DII, patients were categorized into those with the least pro-inflammatory diet and those with a predominantly pro-inflammatory diet.
Of the participants, 36 (58.1 percent) were in remission (RD group) and 26 (41.9 percent) had active disease (AD group). The proportion of patients with overweight/obesity was 69.4 percent (n=25) and 50.0 percent (n=13) in the respective groups. [Eur J Clin Nutr 2026;80:491-497]
Patients in the RD group had a significantly higher WHR (p<0.05) and tended to have central obesity (p<0.01). Pro-inflammatory diet was prevalent across patients in both groups: 58.3 percent (n=21) of RD individuals and 50.0 percent (n=13) of AD participants were in the highest DII tertile. Results of the E-DII were similar.
“In our study, overweight/obesity, elevated WHR, and central obesity were more prevalent in the remission group,” the researchers said. “Additionally, the remission group is characterized by older age and a higher prevalence of metabolic comorbidities, as well as lower levels of physical activity.”
Central adiposity
Visceral fat is metabolically active and a source of pro-inflammatory cytokines, but its clinical impact on IBD activity remains debatable. Some studies report the association of obesity with more severe disease and reduced biological persistence. [Curr Gastroenterol Rep 2022;24:26-36; Curr Opin Gastroenterol 2018;34:112-119; World J Gastroenterol 2023;29:1779-1794]
However, other studies report neutral effects or even a protective benefit of obesity in some patient subgroups. [Gut 2024;73:1376-1387; Br J Nutr 2023;129:157-165; Nutrients 2019;11:1532; Nutrients 2019;11:1398; Nutr J 2019;18:65]
“These heterogeneities may partly explain why, in our sample, greater adiposity in the remission group did not translate into higher objective inflammatory activity,” the researchers said.
“The higher rates of central adiposity in the remission group are intriguing and warrant further investigation, as visceral fat is a known source of pro-inflammatory cytokines,” they added. [Circulation 2021;143:e984-e101; Nat Metab 2024;6:409-432]
In recent reviews, anti-inflammatory dietary patterns, such as Mediterranean-style diets, have been shown to reduce the risk of IBD and lessen inflammation, but the association with objective activity measures, such as endoscopic or radiologic scores, is inconsistent. [BMC Gastroenterol 2025;25:343; Front Nutr 2024;11:1387394]
“Future research should prioritize larger, prospective longitudinal studies to elucidate better the long-term effects of dietary patterns on disease trajectory and to investigate further the interactions between diet, the gut microbiome, and host genetics,” the researchers said.