Type 1 diabetes occurs when the body's own immune system destroys the insulin-producing cells of the pancreas (called beta cells).
Normally, the body's immune system fights off foreign invaders like viruses or bacteria. But for unknown reasons, in people with type 1 diabetes, the immune system attacks various cells in the body. This results in a complete deficiency of the insulin hormone.
In every issue of WebMD the Magazine, we ask our experts to answer readers' questions about a wide range of topics. In our January-February 2011 issue, we asked WebMD's diabetes expert, Michael Dansinger, MD, to answer a question about the link between prediabetes and diabetes.
Q: At my last checkup, my doctor told me I have prediabetes. Does that mean I'll ultimately develop diabetes?
A: Almost everyone who develops type 2 diabetes develops prediabetes first. But not everyone who has prediabetes...
Some people develop a type of diabetes – called secondary diabetes -- which is similar to type 1 diabetes, but the beta cells are not destroyed by the immune system; rather, they are destroyed by some other factor, such as cystic fibrosis or pancreatic surgery.
Understanding Insulin and Type 1 Diabetes
Normally, the hormone insulin is secreted by the pancreas in low amounts. When you eat a meal, sugar (glucose) from food stimulates the pancreas to release insulin. The amount that is released is proportional to the amount that is required by the size of that particular meal.
Insulin's main role is to help move certain nutrients -- especially sugar -- into the cells of the body's tissues. Cells use sugars and other nutrients from meals as a source of energy to function.
The amount of sugar in the blood decreases once it enters the cells. Normally, that signals the beta cells in the pancreas to lower the amount of insulin secreted so that you don't develop low blood sugar levels (hypoglycemia). But the destruction of the beta cells that occurs with type 1 diabetes throws the entire process into disarray.
In people with type 1 diabetes, sugar isn't moved into the cells, because insulin is not available. When sugar builds up in the blood instead of going into cells, the body's cells starve for nutrients and other systems in the body must provide energy for many important bodily functions. As a result, high blood sugar develops and can cause:
Dehydration. The buildup of sugar in the blood can cause an increase in urination (to try to clear the sugar from the body). When the kidneys lose the glucose through the urine, a large amount of water is also lost, causing dehydration.
Weight loss. The loss of sugar in the urine means a loss of calories; therefore, many people with high sugars lose weight. (Dehydration also contributes to weight loss.)
Diabetic ketoacidosis (DKA). Without insulin and because the cells are starved of energy, the body breaks down fat cells. Products of this fat breakdown include acidic chemicals called ketones that can be used for energy. Levels of these ketones begin to build up in the blood, causing an increased acidity. The liver continues to release the sugar it stores to help out. Because the body cannot use these sugars without insulin, more sugar piles into the bloodstream. The combination of high excess sugars, dehydration, and acid buildup is known as "ketoacidosis" and can be life-threatening if not treated immediately.
Damage to the body. Over time, the high sugar levels in the blood may damage the nerves and small blood vessels of the eyes, kidneys, and heart, and predispose a person to atherosclerosis (hardening) of the large arteries that can cause heart attack and stroke.
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If the level is below 70 or you are experiencing symptoms such as shaking, sweating or difficulty thinking, you will need to raise the number immediately. A quick solution is to eat a few pieces of hard candy or 1 tablespoon of sugar or honey. Recheck your numbers again in 15 minutes to see if the number has gone up. If not, repeat the steps above or call your doctor.
People who experience hypoglycemia several times in a week should call their health care provider. It's important to monitor your levels each day so you can make sure your numbers are within the range. If you are pregnant always consult with your health care provider.
Congratulations on taking steps to manage your health.
However, it's important to continue to track your numbers so that you can make lifestyle changes if needed. If you are pregnant always consult with your physician.
Your level is high if this reading was taken before eating. Aim for 70-130 before meals and less than 180 two hours after meals.
Even if your number is high, it's not too late for you to take control of your health and lower your blood sugar.
One of the first steps is to monitor your levels each day. If you are pregnant always consult with your physician.
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