A substantial part of the information in this section has been sourced from:
Diabetes is a condition where there is too much glucose (sugar) in the blood. Glucose is the main source of energy for our bodies and comes from the food we eat.
Insulin is a hormone made in the pancreas, which acts as a key to allow glucose (sugar) to pass from the blood stream into the body cells to provide energy for day to day living.
Diabetes develops when the pancreas is either unable to make insulin or the insulin produced is unable to work effectively. Without insulin doing its job, glucose builds up in the blood stream leading to high blood glucose levels.
See the Guide to Type 1 Diabetes Animation for more information.
Types of diabetes
Other types of diabetes
Why does type 1 diabetes occur?
People with type 1 diabetes have a genetic predisposition that makes them more likely to develop diabetes. It remains unknown why the immune system starts damaging the insulin producing cells of the pancreas in genetically susceptible people. It has been suggested that a trigger is needed for the immune system to start damaging the pancreas. These triggers are believed to be factors in the environment, which are still not fully understood. It is thought that the trigger may be different for different people.
Once triggered, the body’s immune system, which normally protects us from infection, begins to attack the insulin producing cells (beta cells) of the pancreas. The immune system thinks that the beta cells are foreign to the body and starts to destroy them, causing a decrease in insulin production. It can take from a few weeks to many years for all of the beta cells to be destroyed. The pancreas has many beta cells to spare, so symptoms of diabetes do not occur until more than 90% of the cells have been destroyed.
Signs and symptoms
When type 1 diabetes develops blood glucose levels may rise up to five to ten times the normal level. Excess glucose spills over into the urine, drawing water with it and causing frequent urination and dehydration. Thirst increases as the body tries to compensate and an unquenchable thirst results. Excessive tiredness and mood changes are common.
The body is unable to use glucose from food for energy and starts to break down fat and muscle leading to weight loss over weeks or months. The breakdown of fat causes chemicals, known as ketones, to accumulate in the blood, resulting in abdominal pain, nausea and vomiting. If undetected, glucose and ketone levels become very high in the blood stream with severe dehydration and loss of salts from the body. This is called diabetic ketoacidosis (DKA) and coma may occur.
Common Signs and Symptoms
Other Signs and Symptoms
In babies and young infants, signs and symptoms may be less easily detected.
When BGLs are high (more than 15 mmol/L) or when your child is sick it's important to test for ketones. Ketones are acids in the blood formed when body fat is used instead of glucose to provide energy. Ketones are a sign that things are out of balance and your child may be at risk of diabetic ketoacidosis (DKA).
How is type 1 diabetes diagnosed?
To determine the diagnosis of type 1 diabetes, your doctor will perform a test for blood glucose levels and a urine test for glucose and ketones. High levels of glucose and ketones (in the blood and urine) are highly suggestive of type 1 diabetes. It is important not to delay the diagnosis of type 1 diabetes, as it can be life threatening if left untreated.
How common is type 1 diabetes?
Diabetes can occur at any age in children, with 10 - 12 years and 2-3 years being the most common age at diagnosis.
The incidence of type 1 diabetes varies around the world. Countries such as Finland and Sardinia have the highest incidence (35-45 per 100, 000), while the incidence is low in Asian countries. Each year in Australia approximately 20 children per 100,000 aged less than 15 years develop type 1 diabetes.
The number of children developing type 1 diabetes is steadily rising around the world and in NSW by about 3% per year. We do not know why this is happening.
Is there any risk of other family members developing type 1 diabetes?
Although other family members may carry the same ‘at risk’ genes for developing type 1 diabetes, the overall risk is generally low. The risks for family members are estimated as follows:
Facts and figures about diabetes
For more information on general facts and figures about diabetes, click here.
Common myths about type 1 diabetes
It’s important to remember:
• Ambler G.R., Barron V., May C., Ambler E., Cameron F., Caring for Diabetes in Children and Adolescents – A Parents Manual. Second Edition, 2001.
• Silink M., APEG Handbook on Childhood and Adolescent Diabetes. Australasian Paediatric Endocrine Group. Second Edition, 2004.
• Craig M.E., Howard H.J., Silink M., Chan A., The rising incidence of childhood type 1 diabetes in New South Wales, Australia. Journal of Paediatric Endocrinology and Metabolism, 13 (4): 363-372, 2000.