Type 1 diabetes occurs due to a fault in the body’s immune system in which it mistakenly attacks and kills pancreatic beta cells responsible for the production of insulin. As more beta cells are killed, the symptoms of diabetes begin to manifest because the body can no longer control its glucose levels.
However, it is still not known what triggers the initial fault in the immune system. Scientists are aware that genes play a role, but there must be something that plays a role in setting off the immune system, making it turn against itself and leading to high blood sugar levels. Many theories exist, but the truth is yet to be discovered.
Researchers have found that there is a strong genetic link with type 1 diabetes. The disease can develop in people with particular leukocyte antigen genotype, whose function is to trigger the immunological response in the body. Different human leukocyte antigen complexes are also responsible for other autoimmune disorders development. However, these disorders must be triggered by something. So, researchers hypothesize that it may very well be an environmental factor that triggers the development of the disease.
Some of the possible triggers may include:
- Low vitamin D levels. People who lack this vitamin have a higher incidence rate of developing the disease. Thus, the risk for developing type 1 diabetes is higher in those who live in a northern climate. Some populations, as for example, Sardinians or Scandinavians, are much more likely to have the disease-susceptibility genes.
- Viruses. If the virus has some of the same antigens as the insulin-producing cells, the T cells that are to fight the infection, can turn against the insulin-producing cells and destroy them. It may take years for the T cells to destroy the pancreatic beta cells, but the original viral infection is what is supposed to trigger the development of type 1 diabetes. Among viruses similar to the antigens in the beta cells are: Coxsackie virus, Epstein-Bar virus, rotavirus, mumps and German measles.
- Environmental exposures. This includes early exposure to gluten, dairy and drinking water high in nitrates in infants’ diet, and exposure to harmful chemicals, particularly those found in plastic.
To sum up, the etiology of type 1 diabetes is believed to involve the interaction of multiple factors.