Insulin, one hundred years of a milestone

When the body cannot regulate the amount of sugar in the blood, diabetes occurs. Photo: Pexels-Nataliya-Vaitkevich

We live daily, from the cradle to the grave, with countless phenomena that the different sciences deal with. For example, no one escapes the action of gravity, a force that physics deals with, nor is they alien to certain properties of chemical elements and the combinations that they develop and that chemistry studies. But even though it happens like this, neither physics nor chemistry are as close to us as medicine, a discipline that moves between science, technique and art, that of the “doctor-patient” relationship. The reason for this is obvious: we exist in the body, and its maladjustments (diseases) make it difficult, if not impossible, for us to lead full lives. And furthermore, even if one is not affected by such a situation, if the suffering subject is dear to us, we suffer with them.

Banting and Macleod research has benefited millions of people, who make up for the lack of insulin by injecting it

If we look back, we will see that despite being medicine, along with mathematics and astronomy, one of the oldest sciences, it took a long time to become fully “scientific”, that is, to settle on pillars that allowed combat, with much greater security than in the past, some of the evils that affect the human body. The era of “scientific medicine” began during the nineteenth century with the development of physiology, the branch of medicine that deals with the physical-chemical reactions that take place in living beings, a development to which must be added the microbial theory of disease by Louis Pasteur and Robert Koch.

Without forgetting apparently minor but far-reaching advances, such as those carried out by the American dentist Horace Wells, who in December 1844 used ether, that is, nitrous oxide (then called “laughing gas”, due to the stimulating effects it produced) , as an anesthetic to extract one of his teeth himself; or that due to John Collins Warren, assisted as an anesthetist by the dentist William Thomas Morton, who on October 16, 1846, at the Massachusetts General Hospital in Boston, performed the first operation with the same gas; or that of James Young Simpson, who on January 19, 1847, in Edinburgh, used for the first time chloroform to relieve labor pain; or that of Ignaz Semmelweis, who in 1848 discovered one of the causes of wound infection in the dirt on the hands of doctors, introducing antiseptic measures (such as hand washing).


All of the advances that I have just outlined remain, in essence, current, regardless of whether they have been substantially improved. They constitute legacies that medicine has contributed to improvement of the human condition. And today I want to recall another of those permanent legacies, whose “birth” is a century this year: the discovery (isolation) of insulin in 1921. A breakthrough that millions of people turn to daily to combat diabetes.

Physiological dysfunction identified since ancient times – in the 1st century Aulus Cornelius Celsus described it as a disease characterized by a great secretion of urine, constant thirst and considerable loss of body mass – it was not really until the 18th century that an English physician, Mathew Dobson , conducted studies in several groups of patients who suffered from this disease, finding that their blood and urine contained high amounts of sugar. It was believed, however, that it was a substance that the human body could not produce, and that it was formed only under the conditions of disease. It was above all, the French physiologist Claude Bernard, unforgettable author of a paradigmatic book, Introduction to experimental medicine study (1865), who discovered in 1857 that the liver stores a substance, glycogen, which, when needed, is converted into glucose (sugar) that passes into the blood.

When the body cannot regulate the amount of sugar in the blood, diabetes occurs. Until a remedy was discovered, the only way to partially control this disease was to reduce sugar intake, but a lot of natural foods contain sugar, and much more harmful in this regard are processed foods (for example, ready meals, salad dressings, or spaghetti sauces) and soft drinks, barely controlled drugs of our time.

The beginning of the solution came when it was discovered that the pancreas produces (in the so-called “islets of Langerhans”) a protein, which was called “insulin”, whose function is maintain blood sugar balance of the body. Diabetes is due to the fact that the pancreas does not produce enough insulin, although resistance to it can also occur in the body. But they still needed to know how to extract insulin from the pancreas, something they achieved by working with dogs at the University of Toronto, in June 1921, Frederick Banting and John Macleod, with help to perfect the purification method of Charles Best and James Collip. Just two years later, Banting and Macleod received the Nobel Prize in Physiology or Medicine “for the discovery of insulin.”

Those investigations have constituted a blessing for millions of people, which make up for their insulin deficiency by injecting it daily. Initially, it came from the pancreas of animals, mainly pigs or cows, although in 1977 a research team from the United States, led by the Mexican biochemist Francisco Bolívar, managed to produce insulin through genetic engineering (introducing the human insulin gene into the bacterium Escherichia coli). This is the method that is used today. It is only fair, then, that we remember this history, these achievements.

We wish to say thanks to the author of this article for this remarkable material

Insulin, one hundred years of a milestone