The treatment for weight loss was more diverse due to the higher prevalence of obesity. In addition to weight loss medications, many patients seek bariatric surgery to treat obesity. Although bariatric surgery was the most effective way, the patients still get weight gain due to failure to control their lives. The failure weight loss is caused by complex risk factors, such as dietary habits, quality of life, physical inactivity, comorbidities remission rate, and more related to the failure weight loss factors. To explore weight gain factors, the study uses many questionnaires, including demographic parameter and exercise frequency survey, the WHOQOL-BREF assessment, The Bariatric Quality of Life Questionnaire (BQL), the Three-Factor Eating Questionnaire (TFEQ-R18), the Yale Food Addiction Scale version 2.0 (YFAS 2.0), and Depression Anxiety Stress Scales-21 (DASS-21). The investigators assess different factors like quality of life, food addiction, preferences, psychological status, and regular examination parameters to identify reasons for unsuccessful weight loss. The study aims to establish the model for the prediction of risk factors after treatment of weight loss so that the tools will help to manage the best weight control for the future.