Diabetes and Insulin

Some people claim that the discovery of insulin was due to animal experiments.  This is made due to a misunderstanding, or deliberate misrepresentation.  The truth is that diabetes was understood and insulin was applied primrily thanks to human clinical study and autopsy.

Understanding Diabetes

To animal experimenter, Galen (131-201AD)  diabetes was "a weakness of the kidneys which cannot hold back water" - a theory which went unquestioned for centuries (Barach,JH. Annals of the History of Medicine. vol 10. 1928) .  We now know that this was wrong.

It was not until the 1600s that Thomas Sydenham re-discovered "sugary urine" (Venzmer,G. 5000 Years of Medicine. Macdonald. 1972).

In 1766 Dr Matthew Dobson observed human patients to conclude that diabetics pass high volumes of sugar into their urine.  Twenty years later during an autopsy, Dr Thomas Cawley observed that a damaged pancreas was linked with diabetes.

In 1833 a military Surgeon (Dr William Beaumont) explained the role of the pancreas is sugar metabolism.  He drew his conclusions from observing soldiers with war injuries.

In  the 1860s, a French doctor, Laguesse, suggested that the islets in the pancreas had a purpose other than secretion of digestive juices - paving the way for the understanding of the pancreas in diabetes. (Bliss,M. The Discovery of Insulin. Paul Harris Publishing. 1983)

Another animal experimenter, Claud Bernard (1813-1878) assumed that diabetes was a diseases of the liver (Bliss,M. The Discovery of Insulin. Paul harris Publishing. 1983) . He was wrong - metabolism of a fat is a result of diabetes (McDowall,RJS. Handbook of Physiology. 43rd ed. John Murray. 1960) not a cause.  Despite the steady progress in knowledge thanks to clinical (human) study, this put an end to some positive progress.  A typical statement was made by Fluger, who said that the pancreas does not “play any part at all in the origin of diabetes, whether, in fact, there is such a thing as pancreatic diabetes.” (Archives of Experimental Pathology and Pharmacology, 1908;58)

These advances are due to study of humans, not animals.  Hansemann looked into incidents of diabetes and noted that patients who had them also had lesions of the pancreas.  By 1895 he had experimented on dogs and come to the incorrect conclusion that diabetes had nothing to do with the pancreas. (Opie, Eugene L, Diseases of the Pancreas.  It’s cause and nature, Lippincott, 1903)

One of the most valuable advances in understanding diabetes was made by Dr Moses Barron.  Barron was an animal experimenter, and in 1920 was performing an autopsy on a human patient who had suffered from stones i the pancreas and diabetes.  AT this stage, Barron was able to describe the microscopic changes in the islets of Langerhans (part of the pancreas).  Barron explained that his discovery “could be made in no other way, not even by experimental ligation of the ducts in animals.” (Dr Moses Barron “The relation of the Islets of Langerhans to Diabates with Special Reference to Pancreatic Lithiasis” in Surgery, Gynecology and Obstetrics, Vol 31, Nov 1920)

The animal tests 

So far you may be wondering why it is that anyone ever claimed that insulin’s discovery has had anything to do with animal experiments.  However, the claim of dependency on animal use has endured, mainly due to misunderstanding and deliberate misrepresentation of the role of JJR Macleod and Frederick Banting.

Banting and Macleod were awarded a Nobel prize for isolating insulin by extracting it from a dog.  They did not discover insulin, as it had been identified and named before their experiments.  Macleod admitted this. (BMJ, Aug 4 1923, p165-172)  The use of dogs was not necessary, as human tissue was available, but the convention of the time was to use animals, so they followed it.

Soon after these experiments Banting teamed up with Charles Best to give a teenage boy insulin.  Although it has been claimed that it drastically reduced the blood sugar, in fact it only fell by 25%, amid serious side effects – serious enough to prevent a second dose.  A biochemist on Macleod’s team described the insulin as “absolutely useless”, while other scientists described “wrongly conceived, wrongly conducted and wrongly interpreted interpreted set of experiments.” (Francon Roberts, British Medical Journal Dec 16 1922, p1193-4)

The next stage of value was By Collip, the Biochemist who worked with Macleod.  He used chemistry to purify insulin to enable it to be used, and soon after it was harvested from slaughterhouses

Respected writer Bliss sums up the story well: “Banting and Best did not discover insulin...It is particularly important to repeat that Banting’s great idea, duct ligation [in dogs] played no essential part in the discovery.” (Bliss, M The Discovery of Insulin, Uni of Chicago Press, p205)

Until 1936 diabetics were dependent on animal insulin, but it is important to establish that they were dependent on an animal product (which was obtained from the meat industry) as opposed to animal experimentation.  In 1936 synthetic insulin was developed.

This history of diabetes and insulin is verified to reliable medical and historical texts, and shows that diabetics owe nothing to animal experimenters.  The claim that they do does persist, and we would encourage anyone interested to look into this further.

 Other illnesses have been the subject of high profile claims in favour of animal testing.  Read the reality here.

Recommended texts:

“Sacred Cows and Golden Geese” by Dr C Ray Greek and Jean Swingle Greek, Continuum, 2000, p 48-55

Bliss, M The Discovery of Insulin, Uni of Chicago Press