Inclusion Criteria:  body-mass index (BMI) of 40 kg/m2 or higher, or 35 kg/m2 or higher with the presence of at least one comorbidity (type 2 diabetes, high blood pressure, obstructive sleep apnoea, dyslipidaemia, osteoarthritis of the hip or knee) a positive evaluation by our BMDT  Exclusion Criteria:  Presence of H. Pylori, resistant to eradication therapy chronic diarrhoea history of previous bariatric or extensive abdominal surgery