FishGastro Study: Fish Consumption and Gastro-Intestinal Health

Inclusion Criteria: Ulcerative Colitis Patient Group (Group 1): * Aged 18 - 80 * Male or female * Diagnosed with ulcerative colitis * Attending gastroenterology clinic for routine colonoscopy check-up * Willing to increase dietary intake of fish for six months * Willing to undergo a flexible sigmoidoscopy examination Polyps/Resection Group (Group 2): * Aged 18 - 80 * Male or female * A history of polyps in the colon * Attending gastroenterology clinic for routine colonoscopy check-up * Willing to increase dietary intake of fish for six months * Willing to undergo a flexible sigmoidoscopy examination Control Group (Group 3): * Aged 18 - 80 * Male or female * Booked for a colonoscopy examination for the investigation of iron deficiency anaemia of unknown cause (no evidence of macroscopic disease found during examination) * Willing to increase dietary intake of fish for six months * Willing to undergo a flexible sigmoidoscopy examination Exclusion Criteria: Ulcerative Colitis Patient Group (Group 1) and Polyps/Resection Group (Group 2): * Allergic to fish * Receiving anticoagulant therapy * Diabetics * Pregnant or breast-feeding * Organ transplant recipients receiving immunosuppression therapy * Prosthetic heart valve * Allergic to pethidine * Previous diagnosis of bacterial endocarditis Control Group (Group 3): Same as Groups 1 and 2 plus: * Received a diagnosis of colorectal cancer following initial investigative colonoscopy (volunteer will be withdrawn from the study when diagnosed as requiring treatment) * Received a diagnosis of coeliac disease following initial investigative colonoscopy (volunteer will be withdrawn from the study when diagnosed as requiring a modified diet)