What is diabetes?
Diabetes is a disease of the pancreas, an organ behind your stomach that produces the hormone insulin. Insulin helps the body use food for energy. When a person has diabetes, the pancreas either cannot produce enough insulin, uses the insulin incorrectly, or both. Insulin works together with glucose in the bloodstream to help it enter the body's cells to be burned for energy. If the insulin isn't functioning properly, glucose cannot enter the cells. This causes glucose levels in the blood to rise, creating a condition of high blood sugar or diabetes, and leaving the cells without fuel.
What are the common types of diabetes?
There are two common forms of diabetes: type 1 and type 2.
Type 1 diabetes
Type 1 diabetes occurs because the insulin-producing cells of the pancreas are damaged. In type 1 diabetes, the pancreas makes little or no insulin, so sugar cannot get into the body's cells for use as energy. People with type 1 diabetes must use insulin injections to control their blood glucose. Type 1 is the most common form of diabetes in people under age 20, but it can occur at any age. Ten percent of people with diabetes are diagnosed with type 1.
Type 2 diabetes
In type 2 diabetes, the pancreas makes insulin, but it either doesn't produce enough insulin or the insulin does not work properly. Type 2 diabetes may sometimes be controlled with a combination of diet, weight management and exercise. However, treatment also may include oral glucose-lowering medications or insulin injections.
Generally, type 2 diabetes is more common in people over age 40 who are overweight. However, the prevalence of obesity among people in North America has increased the number of people under age 40 who are diagnosed with type 2 diabetes. Nine out of 10 people with diabetes have type 2.
What causes Diabetes Mellitus?
Health care providers do not yet know what causes diabetes. The following factors may increase your chance of getting diabetes:
- Family history of diabetes or inherited tendency
- African-American, Hispanic or Native American race or ethnic background
- Obesity (being 20 percent or more over your desired body weight)
- Physical stress (such as surgery or illness)
- Use of certain medications
- Injury to pancreas (such as infection, tumor, surgery or accident)
- Autoimmune disease
- Hypertension
- Abnormal blood cholesterol or triglyceride levels
- Age (risk increases with age)
- Alcohol (risk increases with years of heavy alcohol use)
- Smoking
- Pregnancy (Pregnancy puts extra stress on a woman's body which causes some women to develop diabetes. Blood sugar levels often return to normal after childbirth. Yet, women who develop diabetes during pregnancy have an increased chance of developing diabetes later in life.)
How is diabetes diagnosed?
The preferred method of diagnosing diabetes is the fasting plasma glucose test (FPG). The FPG measures your blood glucose level after you have fasted (not eaten anything) for 10 to 12 hours.
Normal fasting blood glucose is between 70 and 100 mg/dl for people who do not have diabetes. The standard diagnoses of diabetes is made when:
- A patient has a fasting blood glucose level of 126 mg/dl or higher on two separate occasions; or
- A patient has a random blood glucose level of 200 mg/dl or greater and has common symptoms of diabetes, such as:
- Increased thirst
- Frequent urination
- Increased hunger
- Fatigue
- Blurred vision
- Weight loss
- On occasion, an oral glucose tolerance test may aid in the diagnosis of diabetes or an earlier abnormality that may become diabetes - called impaired glucose tolerance.
Other symptoms may include:
- Slow healing sores or cuts
- Itchy skin (usually in the vaginal or groin area); yeast infections
- Dry mouth
What are some of the long-term complications of diabetes?
Retinopathy (eye disease)
All patients with diabetes should see an ophthalmologist (eye specialist) yearly for a dilated eye examination. Patients with known eye disease, symptoms of blurred vision in one eye or who have blind spots may need to see their ophthalmologist more frequently.
Nephropathy (kidney disease)
Urine testing should be performed yearly. Regular blood pressure checks also are important because control of hypertension (high blood pressure) is essential in slowing kidney disease. Generally, blood pressure should be maintained less than 130/80 in adults. Persistent leg or feet swelling also may be a symptom of kidney disease and should be reported to your doctor.
Neuropathy (nerve disease)
Numbness or tingling in your feet should be reported to your doctor at your regular visits. You should check your feet daily for redness, calluses, cracks or breakdown in skin tissue. If you notice these symptoms before scheduled visits, notify your doctor immediately.
Other long-term may complications include:
- Eye problems, such as glaucoma and cataracts
- Dental problems
- High blood pressure
- Heart disease
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This information is provided by the Cleveland Clinic and is not intended to replace the medical advice of your doctor or health care provider. Please consult your health care provider for advice about a specific medical condition. This document was last reviewed on: 7/10/2008...#7104
