nutrients Article Inflammatory Potential of the Diet and Incidence of Crohn’s Disease and Ulcerative Colitis in the EPIC-Spain Cohort Marcela Guevara 1,2,3, * ,† , Elena Salamanca-Fernández 4,† , Estrella Miqueleiz 1 , Diana Gavrila 2,5 , Pilar Amiano 2,6,7 , Catalina Bonet 8 , Miguel Rodríguez-Barranco 2,4,9 , José María Huerta 2,5 , Luis Bujanda 10,11,12 , María José Sánchez 2,4,9,13 , María Dolores Chirlaque 2,5,14 , Antonio Agudo 8 , Eva Ardanaz 1,2,3 and Jesús Castilla 1,2,3   Citation: Guevara, M.; Salamanca- Fernández, E.; Miqueleiz, E.; Gavrila, D.; Amiano, P.; Bonet, C.; Rodríguez- Barranco, M.; Huerta, J.M.; Bujanda, L.; Sánchez, M.J.; et al. Inflammatory Potential of the Diet and Incidence of Crohn’s Disease and Ulcerative Colitis in the EPIC-Spain Cohort. Nutrients 2021, 13, 2201. https:// doi.org/10.3390/nu13072201 Academic Editors: Gordon W. Moran and Jimmy K. Limdi Received: 12 May 2021 Accepted: 24 June 2021 Published: 26 June 2021 Publisher’s Note: MDPI stays neutral with regard to jurisdictional claims in published maps and institutional affil- iations. Copyright: © 2021 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https:// creativecommons.org/licenses/by/ 4.0/). 1 Instituto de Salud Pública de Navarra, 31003 Pamplona, Spain; estrella.miqueleiz.autor@navarra.es (E.M.); me.ardanaz.aicua@navarra.es (E.A.); jcastilc@navarra.es (J.C.) 2 Consortium for Biomedical Research in Epidemiology and Public Health (CIBERESP), 28029 Madrid, Spain; diana.gavrila@carm.es (D.G.); epicss-san@euskadi.eus (P.A.); miguel.rodriguez.barranco.easp@juntadeandalucia.es (M.R.-B.); jmhuerta.carm@gmail.com (J.M.H.); mariajose.sanchez.easp@juntadeandalucia.es (M.J.S.); mdolores.chirlaque@carm.es (M.D.C.) 3 Navarra Institute for Health Research (IdiSNA), 31008 Pamplona, Spain 4 Instituto de Investigación Biosanitaria de Granada (ibs.GRANADA), 18012 Granada, Spain; esalamanca@ugr.es 5 Department of Epidemiology, Murcia Regional Health Council, IMIB-Arrixaca, 30008 Murcia, Spain 6 Sub-Directorate for Public Health and Addictions of Gipuzkoa, Ministry of Health of the Basque Government, 20013 San Sebastian, Spain 7 Epidemiology and Public Health Area, Biodonostia Health Research Institute, 20014 San Sebastian, Spain 8 Unit of Nutrition and Cancer, Catalan Institute of Oncology—ICO, and Nutrition and Cancer Group, Epidemiology, Public Health, Cancer Prevention and Palliative Care Program, Bellvitge Biomedical Research Institute-IDIBELL, 08908 L’Hospitalet de Llobregat, Spain; cbonet@iconcologia.net (C.B.); a.agudo@iconcologia.net (A.A.) 9 Andalusian School of Public Health (EASP), 18011 Granada, Spain 10 Department of Liver and Gastrointestinal Diseases, Biodonostia Health Research Institute, 20014 San Sebastian, Spain; LUIS.BUJANDAFERNANDEZDEPIEROLA@osakidetza.eus 11 Department of Gastroenterology, University of the Basque Country (UPV/EHU), 20018 San Sebastian, Spain 12 Consortium for Biomedical Research in Hepatic and Digestive Diseases, CIBEREHD, 28029 Madrid, Spain 13 Department of Preventive Medicine and Public Health, University of Granada, 18071 Granada, Spain 14 Departamento de Ciencias Sociosanitarias, Facultad de Medicina, Universidad de Murcia, 30100 Murcia, Spain * Correspondence: mguevare@navarra.es † These authors contributed equally to this work. Abstract: Diet may influence the development of inflammatory bowel disease through the modula- tion of inflammation. We investigated whether the inflammatory potential of the diet is associated with the risk of Crohn’s disease (CD) and ulcerative colitis (UC) in the Spanish cohort of the European Prospective Investigation into Cancer and Nutrition (EPIC-Spain). The study included 32,633 par- ticipants aged 29–69 years. The inflammatory potential of the diet was measured by using an inflammatory score of the diet (ISD) based on a baseline dietary history questionnaire. Cox regression was used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs). During 21 years (674,547 person-years) of follow-up, 32 and 57 participants developed CD and UC, respectively. In multivariable analysis, a one-standard deviation (SD) increment in the ISD (two-unit increase) was associated with a higher risk of CD (HR of 1.71; 95% CI: 1.05–2.80; p = 0.031). By contrast, ISD was not associated with UC (HR for one-SD increment of 0.89; 95% CI: 0.66–1.19; p = 0.436). Our results suggest that consuming a more pro-inflammatory diet may contribute to the risk of CD, supporting that a healthy diet might be beneficial in its prevention. Further, larger studies are needed to verify these findings. Keywords: Crohn’s disease; ulcerative colitis; inflammatory bowel disease; inflammatory potential of the diet; inflammation; prospective cohort study Nutrients 2021, 13, 2201. https://doi.org/10.3390/nu13072201 https://www.mdpi.com/journal/nutrients