Impact of Exclusion Diet in Addition to Anti-TNF Therapy in Crohn's Disease and Ulcerative Colitis: a Prospective, Randomized, Double-arm, Open-label Study

This clinical study protocol aims to prospectively compare the efficacy of standard therapy with anti-TNF agents combined with the Crohn's Disease Exclusion Diet (CDED) versus anti-TNF therapy alone in adult patients with active Crohn's disease or ulcerative colitis. The study will involve patients starting therapy with anti-TNF agents due to active Crohn's disease or ulcerative colitis as per standard clinical practice and in accordance with European (ECCO) guidelines. One group will receive standard medical therapy only, the other will additionally receive dietary advice on how to adhere on a specific exclusion diet, the CDED. By prospectively evaluating the impact of this combined approach, the study seeks to provide evidence on whether CDED can improve response to treatment and therefore improve quality of life for patients with Crohn's disease and ulcerative colitis.

This is a prospective interventional, single-center, double-group, open-label study. Primary objective is to compare the efficacy of CDED in addition to anti-TNF therapy in active CD and UC versus anti-TNF therapy alone. Secondary objective are: * Endoscopic response * Endoscopic remission * Early and late efficacy and persistence of benefits * Biochemical response * Sonographic improvement * Tolerability and compliance to the Crohn's Disease ExclusionDiet (CDED) * Quality of life-Safety of the combination of biological therapy and CDED. The subjects considered are adult patients diagnosed with moderate-to-severe Crohn's disease or moderate-to-severe ulcerative colitis who are starting therapy with an approved anti-TNF agent (infliximab and adalimumab for both UC and CD, and golimumab only for UC).