None listed
Conditions
Brief summary
People with anorexia nervosa often restrict food even when it causes serious harm, but current treatments help fewer than half of those affected. This project aims to understand why the drive to avoid eating becomes so strong. Instead of assuming people with anorexia nervosa simply don’t find food rewarding, the study explores whether avoiding calories may itself feel rewarding. To investigate this, researchers will use a device that delivers tiny amounts of real food during brain scans, allowing them to study how the brain responds during actual eating rather than just looking at pictures. The study will also examine hormones and gut bacteria, which may influence appetite, stress, and decision-making around food. People with lived experience have helped shape the study to ensure it is safe and acceptable. Ultimately, the goal is to uncover the biological mechanisms that sustain self-starvation and identify different subgroups who may benefit from tailored treatments.
Interventions
This study aims to better understand why people with anorexia nervosa restrict food intake, by examining how the brain, body, and behaviour work together to influence eating decisions. Participants with anorexia nervosa and healthy individuals will complete tasks such as brain scans, behavioural assessments, and provide biological samples (e.g., blood and faecal samples), allowing us to understand how the brain responds during caloric avoidance.
This is a cross-sectional observational biopsycho
This study aims to better understand why people with anorexia nervosa restrict food intake, by examining how the brain, body, and behaviour work together to influence eating decisions. Participants with anorexia nervosa and healthy individuals will complete tasks such as brain scans, behavioural assessments, and provide biological samples (e.g., blood and faecal samples), allowing us to understand how the brain responds during caloric avoidance. This is a cross-sectional observational biopsychological sampling study. All assessments and biological samples (see below) are collected at a single time point only, with no intervention administered. • Physiological measures: a trained researcher will measure participant's height, blind weight (participants won't see their weight) and blood pressure. • Online questionnaires: participants will be asked to complete a series of questionnaires to assess eating disorder symptoms, mental health and thinking flexibility (all questionnaires are specified under 'outcomes'). This will take approximately 55 minutes to complete. • Neuroimaging: participants will undergo MRI brain scanning while doing a task where you choose whether to take small sips of a milkshake. This will take approximately 50 minutes. • Actigraphy and sleep: participants will be asked to wear a smart watch for one week to measure sleep, activity, heart rate and stress. • Food diary: participants will be asked to keep a food diary for five days. • Faecal samples: participants will be asked to collect two small faecal samples at home. • Blood samples: a fasting blood sample will be taken by a qualified blood collector in a clinical setting. In total, participation in this study will involve approximately 4 hours and 45 minutes of research activities.
Sponsors
The University of Sydney
Eligibility
Sex/Gender
All
Age
18 Years to 60 Years
Healthy volunteers
Yes
Inclusion criteria
Inclusion Criteria for Anorexia Nervosa (AN) participants • Current diagnosis of AN (restrictive, binge-purge or OSFED atypical-AN (subthreshold AN)) • Age 18 - 60 years • Willing and able to comply with all study requirements, including timing and/or nature of required assessments Inclusion Criteria for Healthy Controls (HC) • Age 18 - 60 years • Body mass index 18.5 - 30 • Weight stability for past 3 months
Exclusion criteria
Exclusion Criteria for Anorexia Nervosa (AN) participants and Healthy Controls (HC) • Inability to undergo MRI examination due to physical (implants or devices) or psychological reasons • Unable to access study location • Use of medications that affect appetite, weight or metabolism e.g. Insulin, Metformin, Ozempic, Seroquel, Vyvanse, GLP-1 agonists, steroids • Antibiotic use in the past 3 months • Active suicidality • Active psychosis • Pregnancy • Diabetes • Unable to speak or read English
Outcome results
None listed