If a patient became sugar-free and blood sugar normal on a basal requirement diet, the caloric intake was gradually increased until sugar appeared in the urine. The tolerance was thus ascertained.
Frederick BantingIntravenous injections of extract from dog's pancreas, removed from seven to ten weeks after ligation of the ducts, invariably exercises a reducing influence upon the percentage sugar of the blood and the amount of sugar excreted in the urine ... the extent and duration of the reduction varies directly with the amount of extract injected.
Frederick Banting