What Is Diabetes?

Diabetes mellitus is a disease of the pancreas (an organ behind your stomach). Normally, the pancreas releases a hormone called insulin that helps your body store and use the sugar and fat from the food you eat.

Diabetes occurs:

When the pancreas does not produce any insulin,or

The pancreas produces very little insulin, or

When the body does not respond appropriately to insulin, a condition called "insulin resistance."

Diabetes is a lifelong disease. As yet, there is no cure. People with diabetes learn to manage their disease to stay healthy.

Why Is Insulin Important?

To understand why insulin is important, it helps to know more about how the body uses food for energy. Your body is made up of millions of cells. To make energy, these cells need food in a very simple form. When you eat or drink, much of your food is broken down into a simple sugar called glucose. Glucose ("sugar") provides the energy your body needs for daily activities.

Your bloodstream transports glucose both from where it is taken into the body after eating (the intestines) and where it is manufactured (in the liver) to the cells where it will be used (muscles, brain, etc.) or stored (in the liver) or converted to fat (also in the liver).

When the amount of glucose in your blood reaches a certain level, your pancreas releases insulin. The insulin carries the glucose into the appropriate cells. As more glucose enters your cells, the level of glucose in your bloodstream drops.

Without insulin, the glucose can't be stored -- which allows the level of glucose in the blood to rise. Too much glucose in the blood is called "high blood sugar." By definition, diabetes is having a blood sugar level of 126 milligrams per deciliter (mg/dL) or more after an overnight fast.

What Are the Types of Diabetes?

Type 1 diabetes. Type 1 diabetes occurs because the insulin-producing cells of the pancreas (called beta cells) are damaged. People with type 1 diabetes produce little or no insulin. People with type 1 diabetes must use insulin injections to control their blood glucose.

The damage to the insulin-producing cells in type 1 diabetes occurs over a period of years. However, the symptoms of type 1 diabetes may occur over a period of days to weeks. Type 1 most commonly starts in people under the age of 20, but may occur at any age.

Type 2 diabetes. Unlike people with type 1 diabetes, people with type 2 diabetes produce insulin. However, the insulin they produce is either not enough or doesn't work properly in the body. When there isn't enough insulin or the insulin is not used as it should be, glucose can't get into the body's cells.

Type 2 diabetes is the most common form of diabetes mellitus. It usually starts in people over age 40 who are overweight. But the rise in obesity in young people has caused a rise in type 2 diabetes in that age group. Some people can manage their type 2 diabetes by controlling their weight, watching their diet, and exercising regularly. Others may also need to take a pill that helps them use their insulin better, or take insulin injections.

Type 2 diabetes can also occur in people who are not obese. [see below: What Are the Risk Factors for Diabetes.]

Gestational diabetes. Gestational diabetes is triggered by pregnancy. Hormone changes during pregnancy can affect insulin's ability to work properly, resulting in high blood glucose levels.

Pregnant women who have an increased risk of developing gestational diabetes are those who are over 25 years old, are above their normal body weight before pregnancy, have a family history of diabetes or are Hispanic, African-American, Native American, or Asian.

Usually, blood glucose levels return to normal after childbirth. However, women who have had gestational diabetes have an increased risk of developing type 2 diabetes later in life.

What Are the Symptoms of Diabetes?

The symptoms of type 1 diabetes often occur suddenly and can be severe. They include:

Increased thirst

Increased hunger (especially after eating)

Dry mouth

Frequent urination

Unexplained weight loss (even though you are eating and feel hungry)

Fatigue (weak, tired feeling)

Blurred vision

Numbness or tingling of the hands or feet

Loss of consciousness (rare)

The symptoms of type 2 diabetes may be the same as those listed above. Most often, there are no symptoms or a very gradual development of the above symptoms. Other symptoms may include:

Slow-healing sores or cuts

Itching of the skin (usually in the vaginal or groin area)

Yeast infections

Recent weight gain

What Are the Risk Factors for Diabetes?

Although the causes of diabetes are unknown, the following risk factors may increase your chance of getting diabetes:

A family history. If a parent or sibling in your family has diabetes, your risk of developing diabetes is increased.

Race or ethnic background. The risk of diabetes is greater in Hispanics, African-Americans, Native Americans, and Asians.

Being overweight. If you are 20% or more over your optimal body weight, you increase your risk of developing diabetes.

Hypertension (high blood pressure).

Abnormal cholesterol levels. Low HDL or "good" cholesterol level under 35 mg/dL and/or a triglyceride level over 250 mg/dL increases your risk.

Age. Your risk of developing diabetes increases progressively as you get older.

Use of certain drugs:

Blood pressure medicines, such as thiazides.

Steroid medicines, such as prednisone or Decadron (dexamethasone).

Hydantoin medicines, such as Dilantin.

Medicines for transplant recipients, such as cyclosporine

Alcohol Use.Years of heavy alcohol intake increases your risk of developing diabetes.

Smoking. Smoking increases your risk .

History of gestational diabetes (developing diabetes during pregnancy) or of delivering babies over nine pounds.

Autoimmune disease. Your body's defense system (immune system) attacks healthy insulin-producing beta cells in your pancreas.

Viruses. Some viruses are thought to play a part in diabetes development.

It is important to note that eating a lot of sugar, in and of itself, does not cause diabetes, but it can lead to tooth decay and obesity.

How Is Diabetes Diagnosed?

If you suddenly experience symptoms of increased thirst, frequent urination, or unexplained weight loss, your doctor may suspect diabetes. To confirm the diagnosis, a fasting plasma glucose test or a casual plasma glucose test will be performed.

The preferred method of diagnosing diabetes is the fasting plasma glucose test (FPG) because it is easy to do, convenient for patients, and less expensive than other tests, according to the American Diabetes Association. The FPG measures your blood glucose level after you have not eaten anything for 10 to 12 hours.

Normal fasting blood glucose is between 70 and 115 mg/dL for people who do not have diabetes. The standard diagnosis of diabetes is made when two separate blood tests show that your fasting blood glucose level is greater than or equal to 126 mg/dL.

Some people have a normal fasting blood glucose reading, but their blood glucose rapidly rises as they eat. These people may have glucose intolerance. If their blood glucose levels are high enough, they may be considered to have diabetes.

The casual plasma glucose test is another method of diagnosing diabetes in which blood glucose is tested without regard to the time since the person's last meal. A glucose level greater than 200 mg/dL may indicate diabetes, especially if the test is repeated at a later time and shows similar results.

The oral glucose tolerance test is yet another method used to detect diabetes, but it is usually only done during pregnancy.

How Is Diabetes Managed?

At the present time, diabetes can't be cured, but it can be treated and controlled. The goals of managing diabetes are to:

Keep your blood glucose levels as near to normal as possible by balancing food intake with medication and activity.

Maintain your blood cholesterol and triglyceride (lipid) levels as near their normal ranges as possible by decreasing the total amount of fat to 30% or less of your total daily calories and by reducing saturated fat and cholesterol.

Control your blood pressure. Your blood pressure should not go over 130/85.

Slow or possibly prevent the development of diabetes-related health problems. You hold the keys to managing your diabetes by:

You hold the keys to managing your diabetes by:

Planning what you eat and following a balanced meal plan.

Exercising regularly.

Taking medicine, if prescribed, and closely following the guidelines on how and when to take it.

Monitoring your blood glucose and blood pressure levels at home.

Keeping your appointments with your healthcare providers and having laboratory tests as ordered by your doctor.

What you do at home every day affects your blood glucose more than what your doctor can do every few months during your checkups.