Obese patients have increased cardiovascular risk and target organ damage (TOD) as compared to people with normal weight. Weight loss reduces cardiovascular risk and TOD. These changes have been associated mainly to changes in inflammatory and pro-atherogenic markers. Office peripheral blood pressure (BP) appears to decrease after bariatric surgery, but information on changes in 24h-ambulatory-BP-monitoring (24h-ABPM) and central-BP(cBP), or about the possible role of renin-angiotensin-aldosterone (RAAS), serotonin(STS) and endocannabinoid(ECS) systems is scarce. Our hypothesis is that the hemodynamic changes mediated by alterations in the RAAS, STS and ECS after weight loss are also responsible for the reduction of TOD.