FGF23 and anemia (phenotype): Since neither C-, nor N-terminal FGF23 evoke phosphaturic effects, posttranslational FGF23 processing adds another layer of complexity to its biology.16,61 Remarkably, some studies have suggested that cFGF23, in fact, antagonizes signaling pathways induced by the intact molecule, thereby inhibiting phosphate excretion.26 This could imply that transient phosphate retention might be favorable in the presence of pathologies whose correction impose a high energetic burden, i.e., restoration of anemia or fighting invading pathogens through inflammatory responses.