Illustration by Derek R. Audette
“Blood is a very special juice.”
Goethe didn’t know the half of it when he penned this line for Mephisto more than 200 years ago.
In those days people believed blood held mystical qualities and was a potent life force. No wonder Mephisto wants the contract for Faust’s soul signed in this “special juice.”
But what exactly does blood do?
Blood transports oxygen to all of our body’s cells, which use it as fuel. Blood sweeps away wastes. Blood conveys messages, in the form of hormones, from one organ to another. Blood hosts the immune system — carrying it where it’s needed.
There’s also blood’s dark side. It can turn against us, afflicting us with cancers of the blood cells, sickle cell anemia, hemophilia and many other diseases, and it can carry infection.
Because of blood’s many roles, a few drops can serve as a window on the state of our health, making it the go-to material for diagnostic tests.
Our view of blood has greatly altered in the last century, when transfusion was perfected. Earlier, bloodletting — draining and discarding a portion of blood — was a standard treatment. Today blood is a valuable treatment itself, with nearly 5 million people in the United States each year needing a blood transfusion.
Medical science continues to expand our understanding of what goes on in blood and how best to marshal its power.
For the latest thinking, read on.