By Billie Rubin, Hemoglobin’s Catabolic Cousin, reporting from the labs of Stanford Blood Center
Red blood cells (RBCs) are born in the bone marrow of our large bones at a rate of 2 million every second! Our bone marrow is like a heavy-duty erythropoietic ward.
And RBCs grow up fast. In about seven days they are ready to toss out their nucleus and DNA and leave the nest to spend all of their 120-day life span traveling down vast arterial highways and capillary byways. They get rid of their interior baggage so they can each carry over 250 million molecules of hemoglobin. While tossing out their DNA makes them beefier, it also limits them as they can’t reproduce or even repair themselves. It’s a wild life.