Human red blood cells (RBC), after differentiating from erythroblasts in the bone marrow, are released into the blood and survive in the circulation for approximately 115 days. In humans and some other species, RBC normally survive in a nonrandom manner. This means that all of the RBC in an age cohort are removed by the reticuloendothelial system at about the same time. In practice there is considerable variation in the lifespan of human RBC. In a normal individual with a mean RBC lifespan of 115 days, this value may vary between 70 and 140 days. Among individuals the mean lifespan varies by approximately ±15%.
Measurement of Red Cell Lifespan and Aging
Image credits: Trent McCallum