The aim of this research is to study the effects of a pomegranate juice on calprotectin levels in patients suffering of inflammatory bowel disease (IBD) in clinical remission. Fecal calprotectin levels, surrogate marker of mucosal inflammation, will be measured from baseline to 12 weeks later (end of intervention). Systemic and mucosal changes of biochemical and molecular inflammatory response markers will be also assessed.

The main purpose of the intervention trial is to assess the possible effect of pomegranate juice consumption on reducing fecal calprotectin (FC) levels in volunteers suffering from IBD with a high risk of clinical relapse. In detail, the objectives of this intervention are as follows: (i) assessing the changes in FC levels in the two groups (active treatment, control) from baseline to 12 weeks later (primary outcome); (ii) investigating the systemic and mucosal modifications of selected biochemical and molecular inflammatory response markers in the two groups after 12 weeks of the intervention compared with baseline (secondary outcomes); (iii) evaluating circulating and urinary ellagitannin-derived metabolites from regular pomegranate juice consumption in the two groups before and after the intervention.

The detailed study protocol is published in the Trials journal.

Inclusion Criteria:

• Patients with Ulcerative Colitis (diagnosed on the base of clinic, endoscopic, and histologic criteria) in clinical remission (SCCAI = 0) from at least three months and in stable therapy (without therapeutic modifications in the three previous months) with mesalazine, immunomodulators and/or biologics.
• Patients affected by Crohn's Disease, particularly involving sigmoid colon and rectum (diagnosed on the base of clinic, endoscopic, and histologic criteria) in clinical remission (CDAI < 150) from at least three months and in stable therapy (without therapeutic modifications in the three previous months) with mesalazine A, immunomodulators and/or biologics.
• Fecal calprotectin at baseline ≥ 100 microg/g.
• Signed informed consent.

Exclusion Criteria:

• Patients affected by Ulcerative Colitis and Crohn's Disease with severe endoscopic disease activity (Ulcerative Colitis: Mayo Endoscopic Score = 3; Crohn's Disease: Simple Endoscopic Score SES-CD > 15).
• Patients on steroid therapy in the two previous months.
• Patients in therapy with warfarin or other anticoagulants.
• Known or supposed hypersensitivity to fruit and/or juice of pomegranate.
• Women in fertile age which refuse to use contraceptives specified in the study (oral contraception, IUD) and breastfeed women.
• Diabetic patients and other patients with severe clinical conditions which the investigator consider to contraindicate patient participation at the study.
• Therapy modifications and/or assumption of experimental therapies within three months before the study inclusion.