This study will test the effects of weekly injections of the glucagon like peptide-1 (GLP-1) agonist semaglutide on energy expenditure and metabolic parameters in a 24 week double-blind, placebo-controlled dose escalation randomized trial. After baseline testing, 52 patients will be randomly assigned to the semaglutide or matching placebo injection group. In addition to taking medication or placebo, all participants will a calorie restricted diet provided by the researchers, providing 600 kcals per day below their estimated baseline requirements. Before and at the end of treatment, weight status, body composition, basal metabolic rate (BEE), 24h energy expenditure, daily total energy expenditure (TEE) for free living, physical activity, energy intake (questionnaire and food table), and hormone parameters for energy homeostasis will be evaluated.