Department of Psychiatry \| Li Ka Shing Faculty of Medicine The University of Hong Kong The Effectiveness of rTMS on Improving Food Cravings and Weight Control in Adults without Serious Mental Illness Introduction The investigators would like to invite participants to participate in an observational study on the efficacy of using magnetic fields to improve food cravings and weight control in adults without serious mental illness. The research leader is Dr. Cheng Pak Wing, Assistant Professor, Department of Psychiatry, Queen Mary Hospital/HKU Li Ka Shing Faculty of Medicine. Please read the following information carefully. If necessary, participants can discuss it with relatives, friends or doctors. If anything is unclear, or if participants would like more information, please ask us. Please carefully consider whether participants are willing to participate in this research. Research Purpose Food cravings are a common experience that can significantly impact an individual's mental and physical health. These intense desires for specific foods often lead to overconsumption of unhealthy foods, contributing to obesity, poor nutritional intake, and associated health conditions. Understanding the neural mechanisms behind food cravings is crucial for developing effective interventions to manage them. rTMS is a non-invasive brain stimulation technique that uses magnetic fields to modulate neural activity in targeted brain regions. Over the years, rTMS has shown promise in treating various mental health conditions, including depression, obsessive-compulsive disorder (OCD) and eating disorders. Research Methods Participants Healthy adults aged 18-65 with self-reported food cravings or weight control issues. Treatment protocol Six sessions of rTMS using the EXOMIND™ device, administered once or twice a week. Each session will deliver 6,300 pulses at alternating frequencies of 12, 15, and 18 Hz, with a total duration of 24 minutes and 30 seconds. The target site would be left dorsolateral prefrontal cortex (DLPFC), determined by the most common used 5-cm rule. The procedure would be conducted in the research centre with medical staff supported. A checklist of potential adverse effects from TMS administration will be referenced from existing literature to monitor tolerability and adverse events during each session. Blood pressure and heart rate will be recorded at the beginning and end of each session. Assessment Participants will be assessed at three time points: baseline (pre-intervention), post-intervention, and four weeks post-intervention. Assessments: Food Cravings Questionnaire-Trait (FCQ-T), Perceived Stress Scale (PSS), Patient Health Questionnaire-9 (PHQ-9), and BMI. Demographics: Age, gender, years of education, place of birth, marital status, number of children, financial condition, household income, family history of eating problems will be collected upon study entry. Medical history in relation to mental illnesses and medications will also be assessed.