By Billie Rubin, Hemoglobin’s Catabolic Cousin, reporting from the labs of Stanford Blood Center
Once upon a time (from early Greek and Roman physicians to the late 19th century), “blood-letting,” now known as phlebotomy, was a very popular practice to cure or prevent illness. The theory was that a mystical equilibrium between several bodily fluids (humours) maintained human life. Excess blood would disturb that balance and result in illness.
The four humours were: black bile, yellow bile, phlegm and blood. Too much black bile made you melancholic, too much yellow bile made you choleric, too much phlegm made you phlegmatic, and too much blood made you sanguine. The four humours were related to the four elements: earth, fire, water and air. All four of these elements were said to be in the blood in the form of humours.
So, next time you see those blood bank phlebotomists out there, remember they are not just collecting blood, they are practicing the most ancient form of healing: bringing equilibrium back to the people.