Andrew Zalisky in Science:
In 19th century New York City, Theodore Gaillard Thomas enjoyed an unusual level of fame for a gynecologist. The reason, oddly enough, was milk. Between 1873 and 1880, the daring idea of transfusing milk into the body as a substitute for blood was being tested across the United States. Thomas was the most outspoken advocate of the practice.
At the time, severe bleeding was often a death sentence. Blood transfusion was practiced, but it was something of a crapshoot. Medical science was still 3 decades removed from discovering blood types. Patients who received mismatched blood suffered discolored urine, itching, and a sometimes-fatal complication: hemolytic shock, wherein their own immune systems attacked the transfused cells.
Doctors in the U.S. were looking for something less risky to stabilize a hemorrhaging patient. Thomas was sure milk was the answer. In 1875, he injected 175 milliliters of cow’s milk into a woman suffering from severe uterine bleeding after an operation to remove her cancerous ovaries. At first, he wrote, the patient “complained that her head felt like bursting.” She soon developed a high fever and an abnormally high heart rate, but recovered a week later. Thomas subsequently performed seven separate milk transfusions, publishing his results in several medical journals, and predicted their “brilliant and useful future.”
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