Iron levels Iron increases hepcidin levels. Represents a feedback mechanism to maintain stable body iron levels. Inflammation  Leads to increased hepcidin levels. Represents a host defense mechanism to limit extracellular iron availability to microbes. Erythropoiesis Increased erythroid activity leads to decreased hepcidin levels. Ensures iron supply for erythropoiesis. Erythropoietic drive overrides both iron sensing and inflammation sensing mechanisms to control hepcidin levels.