Interesting historical facts about Diabetes
Diabetes is an age old disease,
Charak Samhita ,Written aprox. in 4th-3rd th century BC by the famous Ayurved physician Charak- perhaps 1st mentions of sweet urine ( Madhu Meha), If ants would sweep over a place where the person urinated his urine was sweet, it was also tasted by ancient indian doctors for sweetness. The word 
madhu meh literally means madhu (Honey- sweet) and (meha- Clouds- rain) i.e sweet rain. In 1869 Paul Langerhans, senior medical student, discovered that our pancreas is a gland which 
is composed by one million of very small islands. (Perhaps these islands can be compared to the taste buds on our tongue In 1893, the French scientist Gustave Laguesse suggested that these islands - today called the islands of Langerhans -- must produce a hormone, or a substance which is anti-diabetic or that controls the level of sugar in the blood.
The islands of pancreas are of two types called alfa and beta. Beta cells produce insulin. Alfa cells produce another hormone called glucagon which is an antagonist to insulin, which increases the blood sugar level in the blood! If the hormone to control the diabetes is produced by the millions of the islands in the pancreas, and the name in Latin for island is "insula", the scientists decided to baptize such a substance INSULIN, meaning that "it comes from the islands".
The greatest discovery concerning the treatment of diabetes occurred in July of 1921, when two Canadian investigators, Frederick Banting and Charles Best, from the University of Toronto, were able to extract insulin from the pancreas of one dog and inject it into another dog that they had made diabetic by removing from him his pancreas. This experiment proved that indeed insulin controlled the sugar of the diabetic dog!
In 1923 Banting and his associates received the Nobel Prize in Medicine for their discovery of extracting insulin from the pancreas. In 1922 the University of Toronto signed a contract with Eli Lilly Laboratory to extract insulin from the pancreas of pigs and from cows , collected at various slaughter houses, originating the production of Regular Pork and Beef Insulins.
With this manufacturing, finally the physicians had available enough Regular Pork and Beef Insulin to control the sugar in the diabetic patients. The insulin because it is made of proteins it has to be injected subcutaneously because if it is swallowed it will be destroyed by the acid of the stomach, loosing all its value or effect. It need to be refrigerated.
The Regular Insulin by injection had an effect of only 4 to 6 hours and therefore was necessary to give several injections during the day to bad diabetics. In 1936 it appeared the insulin of slow reabsorption or Lente Insulin, allowing with this type of insulin to control the blood sugar with only one injection of Lente Insulin per day.