EV are small membrane particles released by most cell types in response to different stimuli and, represent a new communication modality based on their specific cargo. Furthermore, blood and endothelial cell-derived EV participate in all the stages of the atherothrombotic process and thus, may contribute to explaining the known residual CV risk that patients with obesity and other associated comorbidities still present following BS, even after massive weight loss along with a great metabolic improvement. Previous studies have identified increased endothelial and blood cell-derived EV levels in individuals with T2D or obesity. However, very few studies, with limited sample sizes and conflicting results, have explored the interaction of these two metabolic disorders on the EV profile. On the other hand, although former research groups have shown a significant reduction in EV subtypes after BS, others have reported no significant changes. It should also be emphasized that none of the published studies so far have included patients with or without T2D and a normal-weight control group. Furthermore, the relationship between EV and classical and non-classical CV risk factors has not specifically been assessed, and no consistent results have been reported up to now. Thus, if endothelial dysfunction and/or an abnormal EV profile could be fully reversible after BS is still unclear. We aimed to compare the release of EV from blood and endothelial cells between individuals with obesity with or without T2D before and 1 year after BS, and age and sex-matched healthy controls. We further aimed to explore the relationship between the magnitude of EV concentration changes and the clinical and biochemical outcomes 1-year after BS. Herein, we present all the supplementary fields related to the observational clinical study: “Effects of bariatric surgery on blood and vascular extracellular vesicles in individuals with or without type 2 diabetes".