Fibroblast growth factor-23 (FGF-23) was initially recognized for its phosphaturic function in rare hypophosphatemia disorders (1), with elevated levels associated with various adverse cardiovascular outcomes, such as upregulation of the renin-aldosterone-angiotensin system (RAAS) (2, 3), volume expansion (4), endothelial dysfunction (5), and left ventricular hypertrophy (6). Here, FGF23 is linked to endothelial dysfunction.