Metabolic surgery is an emerging option to treat obesity-related metabolic diseases (e.g., type 2 diabetes) and prevent cardiovascular disease (CVD). Metabolic surgery can profoundly alter the gut microbiota; meanwhile, gut microbiota may affect surgical outcomes. Longitudinal studies that examined pre- to post-surgery changes in gut microbiota and its relation to cardiometabolic health after surgery are limited. Furthermore, few studies have included African Americans, a population with high rates of cardiometabolic diseases. The investigators aim to fill these research gaps by establishing a longitudinal, observational study of metabolic surgery patients and applying multi-omics to identify stool, blood, and/or tissue microbial features related to post-surgery cardiometabolic outcomes. In the current study, the investigators plan to enroll up to 300 patients who undergo metabolic surgery at Vanderbilt University Medical Center and follow them for up to 10 years after surgery. Fasting blood and stool samples will be collected at pre-surgery and 3-month, 1-year, 2-year, and 3-year post-surgery clinical visits. Tissue samples (e.g., biopsies of the liver and adipose and remnants of the stomach) will be collected during operation. Meanwhile, participants will complete a REDCap survey at baseline and 1-year, 2-year, and 3-year post-surgery. Participants' electronic medical records will be used to obtain additional information and facilitate long-term follow-up. The investigators will evaluate pre- to post-surgery changes in the fecal microbiome and fecal and blood levels of metabolites and proteins and the associations of microbiome, metabolites, and proteins with cardiometabolic improvements after surgery. This study will advance our understanding of the role of gut microbiota in metabolic surgery, which may translate into novel approaches to identify and treat obese patients for better cardiometabolic health.