Obesity is a chronic and recurrent metabolic disease associated with serious complications and increased mortality. Bariatric surgery was until recently the only intervention that could lead to significant and sustained weight loss. A better understanding of the endocrine regulation of appetite has allowed the development of new treatments. GLP-1 analogues are already available and a dual treatment of GLP-1 analogue and GIP has recently shown even greater efficacy in terms of weight loss. We present a summary of the known mechanisms of action and clinical data that support the use of these molecules in the treatment of obesity.