Bignall, John. "Who Discovered Insulin," The Lancet 342 (28 August 1993), p. 547.
The usual reply to this question "Banting and Best"; and many might also know that the
discovery was made in Toronto and merited a Nobel prize in 1923. Awarded to Banting and
Best? No - to Banting and Macleod.
Until recently, even those in the university from which Macleod graduated and where he served
as Regius Professor of Physiology would be excused ignorance of his achievement: his sole
memorial being a plaque in the library commemorating a gift of books. Banting and Best, on the
other hand, have their names enshrined in chairs of medical research, memorial lectures, and
educational foundations; and Banting even has a crater on the moon named after him. History is
seldom even-handed in apportioning praise and may be excused for favouring the glamour of an
impoverished lecturer in physiology (Banting) and a medical student (Best) over a successful
professor, especially after Banting accused Macleod of trying to steal the limelight.
A supplement to the Proceedings of the Royal College of Physicians of Edinburgh reviews J. J.
R. Macleod's life and the events in Toronto in the mid-twenties, and notes the recent
rehabilitation of Macleod's reputation. The truth - as usual - is more interesting than the myth.
The myth has it that Banting, sleepless one night noted down "Diabetus. Legate pancreatic ducts
of dogs. Keep dogs alive till acini degenerate leaving Islets. Try to isolate the internal secretions
of these to relieve glycosurea" (sic). According to the myth, he approached Macleod, who
reluctantly gave laboratory space; he then enlisted Best and discovered insulin. The truth is that
ligating pancreatic ducts in dogs was irrelevant - insulin was recovered from the intact pancreas
by a visiting professor of biochemistry, Collip, with Macleod's participation and encouragement.
After the Nobel award, Banting split his prize money with Best, and Macleod his with Collip.
There the dispute should have ended, had Banting allowed it to do so. Instead he publicly scorned
Macleod;s part in the discovery and the "Banting and Best" version became established.
Macleod returned to Aberdeen to the Regius chair in 1928, continued his researches into
carbohydrate metabolism, became a Fellow of the Royal Society, and died, at the age of 58 in
1935. In 1990, lecture halls were named after him in Toronto and Aberdeen, and his gravestone
was restored. Small recompense, perhaps, for his part in one of the most useful discoveries of
Williams, M.W. J. J. P. Macleod: The co-discoverer of insulin. Proc R Coll Phys Edin 1993; 23
(suppl 3); 1-125.