What is type 1 diabetes?

Type 1 diabetes is a lifelong disease associated with high blood glucose levels. It occurs if your body cannot produce any or enough insulin, the hormone that controls the amount of glucose in your blood1. People with type 1 diabetes need to take replacement insulin every day to stay healthy.


What is insulin?


Blood glucose from food is your body's main fuel source, but your body needs insulin to make use of it. Insulin is a hormone – like a chemical signal – released by your pancreas when you eat.

Insulin helps move glucose from food into your body's cells where it can be used as energy. Without insulin, your body cannot absorb glucose and it stays in your bloodstream.

Learn more about insulin therapy


Why are high blood glucose levels a problem?

If too much glucose stays in your blood, it can damage your blood vessels and reduce the supply of oxygen and nutrient-rich blood to your body's organs and nerves.

Over time, this can result in serious health complications, including heart disease, kidney disease, nerve damage and eye disease.
Explore the link between blood glucose, insulin and HbA1C

What causes type 1 diabetes?

If you have type 1 diabetes, your body's own immune system starts to attack the insulin-producing beta cells in your pancreas. Why this occurs is not fully understood, but genetic and environmental factors may play a role2.

Once your beta cells are destroyed, your pancreas will produce little or no insulin at all.

What causes type 1 diabetes

What are the symptoms of type 1 diabetes?

In most cases, type 1 diabetes develops very quickly and early in life. For this reason it is usually – but not always – diagnosed during childhood. Type 1 diabetes symptoms can appear suddenly, and you should seek medical advice immediately if you notice any of the following in either yourself or your child:


  • Excessive urination: as your body expels excess glucose
  • Extreme thirst: resulting from urination
  • Muscle cramps: as fluid loss creates an imbalance in electrolytes – like sodium and potassium – in your blood
  • Rapid weight loss: as your body uses fat for energy when cells cannot absorb glucose
  • Tiredness and fatigue: as energy from glucose cannot reach your body's cells
  • Thrush/genital itching, yeast infection: as glucose in urine provides a breeding ground for fungus and bacteria
  • Blurry vision: caused by high glucose levels in the fluid of your eye (and in rare cases damage to the eye's blood vessels)
  • Sweet or fruity-smelling breath: as acids are released when your body uses non-glucose energy sources

Diagnosing type 1 diabetes

The initial test for type 1 diabetes is a random blood test (taken at any time of day) or a urine test. If your results are above normal, and you have symptoms, you may be diagnosed with type 1 diabetes.

If you have no symptoms, but your urine or blood glucose level is high, another blood test will be taken either before breakfast (to get your 'fasting' blood glucose level) or two hours after a meal.
Normal blood glucose levels and levels that indicate type 1 diabetes are compared below.


I've been diagnosed with type 1 diabetes – what now?

A type 1 diabetes diagnosis for you or your child is likely to come as a shock. The best thing you can do to take control of the situation is to learn as much as possible about the disease and its management.

Remember, most people with type 1 diabetes can live a long and active life – provided they manage their blood glucose levels and overall health well. Use the information in this section and talk to your doctor or nurse to create an action plan that works for you.

I've been diagnosed with type 1 diabetes

Treating type 1 diabetes

Type 1 diabetes is a lifelong chronic disease that demands careful management. You will need to take daily injections of insulin with a pen or pump to keep your blood glucose levels under control.


Learn more about treating type 1 diabetes 

Living with type 1 diabetes

A type 1 diabetes diagnosis does not have to hold you back. But you will need to learn how to manage your blood glucose and adapt your routine for different situations and activities. We have lots of information and resources to help you get started.

Learn how to live well with type 1 diabetes

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