The human gut is host to >100 trillion bacteria with an enteric reservoir of >1 g of endotoxin. Alterations in gut microbiota and impaired intestinal barrier function in patients with CKD/ESRD have been linked to endotoxemia and accumulation of gut-derived uremic toxins leading to insulin resistance, protein energy wasting, immune dysregaulation, and atheroscleroisis. CVD, cardiovascular disease; IR, insulin resistance; PEW, protein energy wasting.