Type 1 Diabetes


What is type 1 diabetes?

Type 1 diabetes, sometimes called insulin-dependent diabetes and juvenile diabetes, can develop at any age but most often occurs in children, teens, and young adults. In type 1 diabetes, a person’s pancreas produces little or no insulin, so insulin treatment is needed for a lifetime.

The causes of type 1 diabetes are not fully known. In most cases, the body’s immune system attacks and destroys the part of the pancreas that produces insulin. This occurs over a period of time. So early on in type 1 diabetes, people may not have any symptoms. It is only when enough of the insulin producing cells are affected and insulin producing cells are affected and insulin levels are low that blood sugar rises and symptoms of diabetes start to occur. Because type 1 is an autoimmune disease, people with other autoimmune, conditions, such as Hashimoto disease or primary adrenal insufficiency (also known as Addison's Disease), are more likely to develop type 1 diabetes. Overall, cases of type 1 diabetes seem to be increasing.

What are the symptoms of type 1 diabetes?

The symptoms of type 1 diabetes can look like other conditions or medical problems. If you (or your child) have these symptoms, talk with your doctor as soon as possible.

  • Increased thirst
  • Increased urination
  • Constant hunger
  • Weight loss
  • Blurred vision
  • Constantly feeling tired

How is type 1 diabetes diagnosed and treated?

Your doctor will use blood tests to diagnose diabetes. A blood glucose level above 125 mg/dL after fasting overnight or above 200 mg/dL after eating may indicate diabetes. Your doctor may also take a medical history and order further blood tests to rule out type 2 diabetes.

People with type 1 diabetes must have daily injections of insulin to keep a normal level of glucose in the blood. Blood glucose is kept under the best control with three or more injections per day, or when insulin is delivered throughout the day with an insulin pump. A healthy diet, exercise, and regular monitoring of blood glucose levels are also important to manage diabetes.

How do you monitor blood sugar levels?

To monitor your blood glucose, you first stick your finger or forearm with a special lancet (a needle) to get a drop of blood, which you put on a chemically-treated paper strip. Then you insert the strip into a small computerized machine (blood glucose meter) that reads the blood glucose from the strip. Your blood glucose level shows up as a number on a screen. You can use these blood glucose readings to adjust the doses of insulin that you take every day.

Your doctor or diabetes educator will discuss the various types of available strips and meters and prescribe one for you. They will also talk with you about how often to check your glucose.

A newer technology called continuous glucose monitoring measures glucose levels every few minutes throughout the day and night. It uses a device called a sensor that is inserted under the skin. The sensor then transmits information about glucose levels to a small monitor (about the size of a cellphone).

When should you see your doctor?

If you or your child have symptoms or a family history of diabetes, ask your doctor if testing is needed. Having diabetes requires daily care. All general physicians (family doctors, internists, primary care physicians) can diagnose and treat diabetes. Some people, especially children and adolescents, see an endocrinologist, a specialist in diabetes and other hormone-related conditions, for treatment.

Questions to ask your doctor

  • What can I (or my child) do to keep blood glucose level on target?
  • What should I (or my child) eat?
  • Which medicines do I (or my child) need?
  • What type of exercise is best for me (or my child)?
  • How often should I (or my child) check blood glucose levels?
  • Should I (or my child) see a diabetes educator?
  • Should I (or my child) see an endocrinologist?
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The Hormone Health Network is the public education affiliate of the Endocrine Society dedicated to helping both patients and doctors find information on the prevention, treatment and cure of hormone-related conditions.

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