MRI Based Study to Assess Brain-gut Axis in Obesity

Inclusion Criteria:

• Aged 18-45, male and female (females will have the study days arranged during theearly phase of the menstrual cycle).
• Body mass index (BMI): normal weight participants ≥ 19 and ≤ 25 Kg/m2, and obeseparticipants > 30 Kg/m2
• Able to give voluntary written informed consent to participate in the study
• Able to understand the requirements of the study
• Apparently healthy: no medical conditions which might affect study measurements (judged by health questionnaire, and blood screening)

Exclusion Criteria:

• Any reported history of neurological or gastrointestinal disorders
• Any reported history of surgery that could affect gastrointestinal function (e.g.colectomy, small bowel resection)
• Abnormal screening procedures including depression and eat restriction
• Laboratory results that are clinically significant, including diabetes, dyslipidemia,pancreatitis, or untreated hypertension.
• Contraindications for MRI scanning i.e. metallic implants, pacemakers, history ofmetallic foreign body in eye(s) and penetrating eye injury, assessed by standard MRIsafety questionnaire.
• Under medication (expect aspirin/paracetamol), antibiotic or prescribed probiotictreatment in the past 12 weeks.
• Following a medically- or self-prescribed diet during the two weeks prior to thepre-study examination and until the end of the study.
• Reported weight loss or gain ≥ 10 % of bodyweight during the six months period beforethe pre-study examination
• Pregnancy or breastfeeding declared by candidate
• Smoking
• Left-handed assessed by handedness questionnaire. This is to control for brain'slateralisation effects (activation in one side of the brain) that may show variationsbetween left and right handed participants.
• Participation in another clinical or research study within the previous 3 months ofthe study
• Cannot lie flat or exceeding the scanner bed weight limit of 250 kg.
• Poor understanding of the spoken and/or written English language