by EBSCO Medical Review Board
(Insulin Dependent Diabetes Mellitus; Juvenile-Onset Diabetes; Ketosis-Prone Diabetes; "Brittle" Diabetes; Diabetes Mellitus Type 1; Diabetes, Type 1)


Type 1 diabetes happens when the body does not make enough insulin. Insulin is made in the pancreas. It helps to move glucose out of the blood and into cells. The cells need this glucose for energy.

Type 1 diabetes leads to a build up of glucose in the blood. This can cause damage to blood vessels, nerves, and organs over time. Diabetes also makes it hard for the body to get energy it needs to function.


Type 1 diabetes happens when the pancreas does not make enough insulin. It is most often caused by a problem of the immune system. For unknown reasons, the body's own immune system attacks the pancreas. The damage makes it impossible for the pancreas to make enough insulin. There may be something in genes that causes this to happen.

The Pancreas
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Risk Factors

Type 1 most often appears in children and young adults. It is also more common in people who have family members with it.


Symptoms may be:

  • Urinating more often, especially at night
  • Bedwetting
  • Feeling tired and weak
  • Being very thirsty
  • Hunger
  • Weight loss
  • Belly pain

Ketoacidosis can happen when a person’s glucose gets very high. It can be deadly if it is not treated right away.


The doctor will ask about symptoms and past health. A physical exam will be done. A blood test will show the glucose levels. Levels higher than normal levels show diabetes. The blood may be tested with a finger prick and confirmed with blood sent to a lab. The lab can also look for:

  • Insulin level or C-peptide tests to see how much insulin is being made by the pancreas
  • Tests that look for antibodies that are working against the pancreas


The goal is to keep blood glucose levels at close to normal levels. The health care team and patient will work together to make a plan for control. The plan may change over time but focus on keeping blood glucose balanced and decreasing the risk of problems. Treatment includes a combination of medicine and healthy habits:


All people with type 1 need to take insulin. It will replace the insulin that their body does not make. It can be given by injection, inhaler, or by a pump that gives it in small amounts during the day. The amount will need to be balanced based on activity and food for the day. Too much insulin can cause problems. It can lead to very low levels of glucose called hypoglycemia. A diabetes plan and education can keep these events low.

Pamlintide may be used if insulin alone is not enough. It may help those who are having a hard time with blood glucose control after eating.

Healthy Habits

Foods, activity, and illness are just a few things that affect blood glucose levels. A good treatment plan will include these factors to keep blood glucose balanced. Regular blood glucose checks are an important part of this plan. They will help to guide insulin doses and alert for dangerously high or low glucose levels.

A balanced diet and regular exercise can also help. They can cause immediate change in blood glucose and reduce the risk of long term problems.

Reduce Risk of Complications

Over time, high blood glucose levels can cause damage to eyes , kidneys , and nerves . It can also cause slow healing, especially on feet . Good blood glucose control can help to manage these risks. The care plan will include a check of immediate and long term blood glucose control. The care team and patient will both work on a plan for good health.

Exercise and diet can also help to prevent or lessen complications. They can keep the heart and blood vessels as healthy as possible.

Other Options

A pancreatic islet cell transplant may be done in people who are not helped by other methods. It uses donor cells from the pancreas called islet cells. The new cells can make insulin. Some people may no longer need insulin after the transplant. Not all care centers offer this treatment.

A pancreas transplant may be done if other methods do not work. It is often done with a kidney transplant . This surgery may cause other problems, such as infection or organ rejection.


Type 1 diabetes cannot be prevented.


American Diabetes Association 

National Institute of Diabetes and Digestive and Kidney Diseases 


Canadian Diabetes Association 

Public Health Agency of Canada 


American Diabetes Association. Standards of medical care in diabetes-2019. Diabetes Care. 2019. Jan; 42 (Suppl 1):S1-193.

Diabetes mellitus type 1. EBSCO DynaMed website. Available at: Accessed November 1, 2020.

Type 1 diabetes. American Diabetes Association website. Available at: Accessed November 1, 2020.

Type 1 Diabetes. National Institute of Diabetes and Digestive and Kidney Diseases website. Available at: Accessed November 1, 2020.

9/11/2014 DynaMed Systematic Literature Surveillance  : Tovote KA, Fleer J, et al. Individual mindfulness-based cognitive therapy and cognitive behavior therapy for treating depressive symptoms in patients with diabetes: results of a randomized controlled trial. Diabetes Care. 2014;37(9):2427-2434.

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