Weight Loss Maintenance and Compensatory Mechanisms Activated With a Very-low Calorie Diet

Very-low calorie diets are relatively safe and effective in inducing significant weight loss, when used in selective individuals and under clinical supervision. However, weight loss maintenance in the long-term remains the main challenge, with many experiencing a significant weight regain. Several compensatory mechanisms are activated under weight reduction, both at the level of energy intake (such as increased appetite) and energy expenditure (such as reduced energy expenditure), and increase the risk of relapse. The main aim of this study is to compare the effect of two multidisciplinary lifestyle interventions on weight loss maintenance at one year, after initial weight loss during 8 weeks very-low calorie diet. Participants will be allocated (non-randomly) to either an outpatient program in the obesity unit of the local hospital, or to an inpatient program consisting of a "continuous care" intervention, with three intermittent stays (each with three-week duration) in a rehabilitation center over a one year period. Moreover, the investigators aim to assess the impact of weight loss (achieved with a very low calorie diet) and weight loss maintenance on compensatory mechanisms activated during weight reduction.