Iron-regulatory hormone that acts as an erythroid regulator after hemorrhage: produced by erythroblasts following blood loss and mediates suppression of hepcidin (HAMP) expression in the liver, thereby promoting increased iron absorption and mobilization from stores. Promotes lipid uptake into adipocytes and hepatocytes via transcriptional up-regulation of genes involved in fatty acid uptake. Homodimer; disulfide-linked. May form heteromeric complexes with C1QTNF2 and C1QTNF12 and, to a lesser extent, with C1QTNF5 and C1QTNF10. N-glycosylated. Belongs to the adipolin/erythroferrone family.