What is diabetes?

We all like sugar. Our bodies are programmed to love the sweet taste because we need sugar in the form of glucose. Glucose is the sugar that the body uses to make energy. When we eat the body breaks down the food into glucose, which then enters the bloodstream to be taken to all of the cells in the body.

As the level of glucose rises in the blood, insulin, a hormone, is released from the pancreas, which is a gland that sits behind the stomach and also helps digestion. The insulin attaches to the body’s cells, which opens channels in the cell walls for glucose to enter. The cell then uses the glucose to make energy in the form of ATP in little organelles called mitochondria. The body needs this energy to be able to function.

Therefore, insulin lowers the glucose in the bloodstream by opening the cells so that the glucose can leave the bloodstream and enter into and help feed the cells. If we didn't have insulin, the glucose in the blood would remain high and the cells would starve.

Diabetes Mellitus (diabetes, or DM), is a group of metabolic diseases which is characterized by hyperglycemia (too much glucose in the blood). This happens when there either isn’t enough insulin (Diabetes type 1), or the cells become resistant to allowing the insulin to open the glucose channels (Diabetes type 2). When glucose can’t get into the cells, the levels in the blood increase, and the cells starve, being unable to make adequate energy for the body’s needs. The elevated levels in the blood vessels can then cause damage to those vessels.

Symptoms of high blood sugar can include: blurred vision; drowsiness; dry mouth; flushed and dry skin; fruit-like breath odor; increased urination; loss of appetite; stomachache, nausea, or vomiting; tiredness; troubled breathing (rapid and deep); and unusual thirst.

When insulin levels are too low and glucose levels too high, there is weight loss because the glucose can't enter the cells (type 1 diabetes). When the cells are resistant to insulin, the insulin levels rise. Insulin causes the body to hold onto fat, and there is weight gain (type 2 diabetes).

When the glucose is too high in the bloodstream, the glucose begins to “glycosylate,” or attach, to proteins in the blood and blood vessels, causing damage to the vessels. This is what causes the damage in the body related to diabetes. Over time, this glycosylation can lead to blindness, kidney failure and nerve damage (neuropathy). These types of damage are the result of damage to small vessels, referred to as micro-vascular disease.

Diabetes is also an important factor in accelerating the hardening and narrowing of the arteries (atherosclerosis), leading to not enough blood to the legs and feet, strokes, coronary heart disease, and other large blood vessel diseases. This is referred to as macro-vascular disease.

There are two main types of diabetes, simply named as type 1 and type 2. Diabetes Mellitus type 1 (DM 1) is generally a disease that starts in childhood, though more rarely it can start in adulthood as well. No one knows the absolute cause of DM 1, but it is characterized by a destruction of the beta cells in the pancreas that make insulin. There seems to be an autoimmune problem in which the body starts to destroy its own cells. Therefore, in DM 1 there is not enough insulin, and insulin shots are necessary for the patient to survive. If the patient does not have enough insulin, he/she will go into a condition called ketoacidosis, and will die without help. This is a very serious condition.

Symptoms of ketoacidosis that need immediate hospitalization include: flushed dry skin, fruit-like breath odor, ketones in urine, passing out, troubled breathing (rapid and deep) and possibly fever.

Diabetes Mellitus type 2 (DM 2) is much more prevalent. About 90% of the diabetes in the United States is DM 2. DM 2 is a condition in which the cells become resistant to the insulin, so that the glucose cannot get into the cell even when the insulin attaches to the cell receptor. Often the body makes more insulin to try and get the cells to open, so most people with DM 2 will have higher than normal levels of insulin. These patients will not develop ketoacidosis, and so do not die quickly if their blood sugars rise, but usually die from the long-term complications of glycosylation. The medicines for DM 2 are designed to either increase insulin or assist the cells to be more receptive to the insulin.

DM 2 has been considered a genetic disease, but recently many people have been diagnosed that do not have a family history. I believe that this disease is a disease of our modern lifestyle, and comes on much easier if there is a genetic tendency towards it.

In my next blog we will discuss the possible causes of diabetes.

Until we meet again,
Dr. Judi