This investigation aims to apply and test the feasibility of an acceptance, mindfulness and compassionate-based intervention structured for inflammatory bowel disease patients. LIFEwithIBD programme for inflammatory bowel disease thus comprises 9 weekly group sessions, lasting 1 and a half hour each, run in small groups at a Gastroenterology Service at the Coimbra's University Hospital. For each week participants have assigned homework (e.g., mindfulness exercises). The efficacy of LIFE-IBD Group Intervention to improve quality of life, mental health, and disease activity-related scores will be tested in a sample of Portuguese patients. Additionally, this study expected that the observable changes after the intervention completion will be attributed to changes in emotional regulation processes and maintained over the follow-up periods.

The sample will include diagnosed inflammatory bowel disease patients recruited at a Gastroenterology Service at the Coimbra's University Hospital, a national reference centre for IBD. Patients will be approached by their doctor to assess their level of interest in the investigation. Patients who demonstrate interest will go through a Screening interview conducted by a psychologist that aims explain the structure and arms of the investigation, to collect demographic data, and whether the patient meets the inclusion criteria for the study. After sample collection, participants will be randomly assigned to one of two conditions: experimental group (n=75) or control group (n=75). The experimental group will be divided into five subgroups of 15 participants. The first group will function as a pilot group to test the suitability of the programme. The intervention will include 8 weekly sessions, with the duration of 90 minutes each. Groups will have two therapists with experience in ACT and CFT-based interventions. All participants will continue on receiving the recommended pharmacological treatment for IBD (TAU). This will allow the comparison between the participants receiving the LIFE-IBD Group Intervention+TAU (experimental group) and the participants only receiving TAU (control group). The frequency of engagement with the programme at home practises will be analysed as moderator of the efficacy of the programme. Both groups will concurrently complete a protocol of measures to assess main three areas: a) psychological processes; b) quality of life and psychopathology; c) current medical status. These assessments will occur in four different times: before the start of the LIFEwithIBD programme M0), after the final session of the programme (M1), and 3 (M2) and 6 months (M4) after that.

Inclusion Criteria:

• diagnosis of IBD for more than 6 months (CD or UC)

Exclusion Criteria:

• having started new treatment for IBD in the previous 6 months (in the case of anti-TNF and immunosuppressive therapy) or 2 months (in the case of steroid or aminosalicylate therapy)
• cognitive impairment;
• currently undergoing any form of psychological intervention;
• current diagnosis of severe psychiatric illness (severe depression, psychotic illness, bipolar disorder, substance abuse) or suicidal ideation;
• diagnosis of other serious health condition;
• pregnancy.