Anorexia iN Cancer Patients: ANCHOR

Inclusion Criteria: * Inclusion criteria: Cohort A 1. Patients with stage IV gastric or GOJ adenocarcinoma or locally advanced non-resectable adenocarcinoma 2. Histologically proven adenocarcinoma, squamous cell carcinoma or poorly differentiated carcinoma 3. Patients should be chemotherapy or immune therapy naïve (for their current diagnosis). 4. Patient must be 18 years of age or above. 5. Patient must be able to understand the study information given to them and be willing to give consent for trial participation. 6. Patients should be commencing a course of palliative chemotherapy treatment with the upper GI team at the Christie Hospital In addition the above patients enrolled in cohort B must meet the following criteria Inclusion criteria: Cohort B 1\. Be physically able to perform moderate exercise (to their own tolerance) on a stationary bicycle or treadmill In addition to the above patients in cohort C must meet the following criteria Inclusion Criteria: Cohort C 1. Histologically proven adenocarcinoma or poorly differentiated carcinoma 2. Patients should be chemotherapy or immune therapy naïve. 3. Patients must be able and willing to fast for 8-10 hours. 4 5.1 Patients in the anorexic group must have completed the FAACT AC/S questionnaire and scored ≤24 in total score and ≤ 2 in the appetite specific question. 5.2 For inclusion in the non-anorexic group patients must have completed the FAACT AC/S questionnaire; the total score should be \> 37 and ≥3 for the appetite specific question. Inclusion criteria: Cohort D - healthy controls 1. Participants must be 18 years of age or above. 2. Participants must be able and willing to fast for 8-10 hours. 3. Participants must be able to understand the study information given to them and be willing to give consent for trial participation. 4. Participants must have completed the FAACT AC/S questionnaire and scored ≤24 in total score and ≤ 2 in the appetite specific question, for the anorexic group. For inclusion in the non-anorexic group the total score should be \> 37 and ≥3 for the appetite specific question. Exclusion Criteria: * Participants are excluded from the study if any of the following criteria apply: Exclusion criteria Cohort A: 1. Patients unable to give informed consent 2. Patients not undergoing systemic anti-cancer treatment at The Christie hospital, for example patients not deemed fit enough for treatment, patients having alternative treatments such as radiotherapy or surgery, or patients referred for 2nd opinions. Exclusion criteria Cohort B: 1. Recent myocardial infarction or stroke 2. Recent abdominal, eye or thoracic surgery 3. A recent respiratory tract infection (within 3 weeks) 4. Any chest pain on the day of the test 5. A positive COVID-19 test Exclusion Criteria Cohort C \& D : all patients and healthy volunteers 1. Symptoms of dysphagia of any cause, oesophageal or gastric obstruction (assessed via medical history/O'Rourke score). Patients with O'Rourke score ≥2 will be excluded. 2. Presence of oesophageal stent or any other kind of feeding aid (nasogastric tube, nasoduodenal tube, gastrostomy, jejunostomy) 3. Presence of brain metastases or any kind of brain tumor including benign pituitary adenomas. 4. Histological diagnosis of neuroendocrine tumor, or mixed tumor. 5. Previous gastro-duodenal surgery. 6. History of Inflammatory Bowel Disease (Ulcerative colitis, Crohn's disease). 7. History of Coeliac disease. 8. History of endocrine disease (Diabetes mellitus, Thyroid disease, Cushing's) 9. Significant past or present eating disorder e.g. anorexia nervosa, bulimia nervosa. 10. Current active infection (general or intestinal). 11. Chronic use of immunomodulatory drugs (steroids, immunosuppressant drugs, recent use of corticosteroids would require a two week washout period prior to study assessments). 12. Chronic use of NSAIDS or aspirin. (Periodic use can be accepted). 13. Patients with pacemakers. (Contraindication for BIA). 14. Allergy to any of the ingredients of the meal test or unwillingness to consume the particular meal (Heinz Chicken soup or Heinz Mushroom soup).