What Causes Diabetes?

Diabetes is both a common and potentially devastating disease. If not well controlled, it can lead to complications that affect virtually every major organ system in the body. How much do we really understand about the cause of diabetes?

To better understand the cause of diabetes, let's get a basic understanding of how our blood sugar is controlled. The pancreas is an important organ that houses the powerful insulin producing Islets of Langerhans. The Islets of Langerhans are able to sense the amount of glucose in thblood stream and produce just enough insulin to allow glucose to be taken up and used by the cells of the body for energy production. Thus, glucose that enters your blood stream after a meal is quickly utilized, returning your blood sugar levels to normal. What is it that goes wrong with this mechanism that results in the manifestations of diabetes?

There are actually two types of Diabetes which are classified as Type 1 and Type 2. By far the most common is Type 2 diabetes which accounts for 90% of all diabetics. This form of diabetes is generally seen in older persons. Type 1 diabetes is more common in children and young adults.

What's the difference between the two types of diabetes?

In Type 1 diabetes for some unknown reason, the Islets of Langerhans are destroyed by the body's own immune system, altering their ability to produce insulin. Thus cells are unable to take up glucose effectively and convert it into energy for use by the body. You essentially see elevation in blood sugar levels with cell starvation due to lack of insulin. Plus, the additional glucose that remains in the blood stream directly contributes to the development of the long term complications we see with diabetes.

Why does the body attempt to destroy it's own Islets of Langerhans? No one knows for sure but there have been various theories proposed including exposure to a virus or toxin during childhood. Research is now looking at the possibility of transplanting Islets of Langerhan cells from Wnormal individuals into diabetics. This would require the use of immunosuppressive drugs to prevent the recipient's body from destroying the transplanted cells which would have significant side effects.

In Type 2 diabetes, insulin is produced normally, but the tissues and cells of the body are unable to use the insulin manufactured by the Islets of Langerhans.. For some reason they have become resistant to the effects of their own insulin. Insulin continues to be made, but the cells are unable to recognize it and use it effectively..This is known as insulin resistance. Therapy is aimed at increasing the sensitivity of cells to the circulating insulin as well as decreasing levels of glucose consumed in the diet to lower blood sugar levels.

When considering the cause of diabetes, it's important to consider the strong component that heredity plays. The hereditary component is so strong that if one twin has Type 2 diabetes, the chance of the other twin developing the disease is almost 100%! Heredity plays less of a role in Type 1 diabetes with only about half of identical twins developing the disease when one is affected. Other factors that play a role in the development of Type 2 diabetes include obesity which increases insulin resistance, aging, and lack of physical activity. As previously mentioned, the cause of Type 1 diabetes is speculated to be exposure to a virus or toxin that causes the insulin producing Islets of Langerhans to be destroyed.

It's obvious we still have much to learn about the exact cause of diabetes. Thew's ongoing research addressing these issues as well as looking for potential new treatments. Stay tuned for an article on the treatment of diabetes!