IN the bodily economy of animals, including man, insulin has evolved into the premier regulator of storage and conservation of the three major foodstuffs. Even the growth hormone of the pituitary gland, which promotes skeletal growth and protein synthesis, requires the presence of insulin for optimum anabolic action. Insulin is produced solely by the beta cells of the islets of Langerhans in the pancreas, and its total daily output is about 1 to 2 mg. The biologic effectiveness of the hormone is very high; about 10 molecules per cell may induce a characteristic hormonal effect.Insulin is a simple protein . . .