What is Type 1 Diabetes?

Type 1 Diabetes (T1D) is an autoimmune disease destroying our body’s ability to process sugar by attacking the beta cells in our pancreas that produce the hormone insulin. Insulin helps convert sugar into the fuel our bodies need. Without insulin, sugar builds up in our bloodstream in life-threatening amounts. Multiple times each day insulin needs to be injected into the body of someone living with T1D.


The cause of T1D is unknown. Here's what we do know:

  • diet and lifestyle are NOT factors in the onset of T1D;
  • T1D develops in stages, beginning before symptoms appear;
  • destruction of insulin-producing beta cells is due to damage inflicted by your immune system;
  • something triggered your immune system to attack your beta cells;
  • 50 genes have been identified as increasing a person’s risk of developing T1D, but genes are only part of the cause;
  • the rates of T1D cannot be explained by genetics alone, which means the environment must have a role;
  • researchers are looking for triggers, such as viral infections and particular molecules within our environment and foods;
  • 90% of people living with T1D have no family history of the condition;
  • however, having a family history of T1D puts people at higher risk of developing the disease;
  • T1D does not discriminate. People of all ethnic backgrounds have T1D;
  • the majority of people are diagnosed with T1D before 19.


Fruity Breath

High level of ketones in the blood can lead to an unusual wine-like odour in your breath. It might be sweet smelling or like fruit.

Weight Loss

If your body is losing sugar in your urine instead of absorbing it you will lose weight because your body isn’t getting enough calories from the food you eat.​

Blurred Vision

High levels of blood sugar pull fluid from your tissues, including the lenses of your eyes. This affects your ability to focus.​

Extreme Thirst

One of the first early warning signs is increased thirst and bathroom breaks. Dehydration can lead to nausea, dizziness, headaches and fainting and diabetic ketoacidosis (DKA). 

Frequent Urination

Frequent urination or Polyuria occurs when there is excess sugar in the blood. Normally, when your kidneys create urine, they reabsorb all of the sugar and direct it back to the bloodstream. With T1D, excess glucose ends up in the kidneys where it pulls more water and results in more urine.

Diabetic Ketoacidosis

Having very high blood-glucose levels for an extended time can lead to Diabetic Ketoacidosis (DKA). DKA happens when the body starts to burn fat and body tissue for energy. This releases toxic acids called ketones. DKA is a life-threatening condition, symptoms include heavy or laboured breathing, nausea and vomiting, excessive thirst, stomach pains and stupor or unconsciousness.

How is T1D diagnosed?

The quickest and often the first option for testing for T1D is a random glucose test measuring a patient’s current blood sugar.

This is a blood test typically conducted in the morning after fasting overnight. The fasting helps give doctors a clear look at how the body manages blood-sugar levels without the impact of food intake.

After fasting and having an initial blood test, people drink a sugary drink and then have their blood sugar tested over the course of approximately two hours. This shows the benchmark sugar level without outside influences and later measures how the body responds to carbohydrate (sugar) intake.

The most comprehensive test is the hemoglobin A1c test. This blood test shows the average blood-sugar level for the past two or three months.

While most tests check for antibodies, this test measures how much C-peptide is in a person’s blood. Peptide levels typically mirror insulin levels in the body. Low levels of C-peptide and insulin can point to T1D.

This test looks for antibodies mounted against a specific enzyme in beta cells. Both the IA-2A and GADA tests are common T1D antibody tests.

Looks at antibodies targeting an enzyme that is specific to beta cells.

This test identifies a type of islet cell antibodies present in up to 80% of people with T1D.

This test looks for antibodies built against a specific enzyme in the insulin-producing pancreatic beta cells.C77

There is a period of time following diagnosis when most people experience a “Honeymoon Phase” in which their remaining beta cells still function and the body is able to produce some of its own insulin. The Honeymoon Phase typically lasts a few months to a year post-diagnosis. During this time physicians will support blood-glucose management with low-dose insulin treatments. Eventually, the remaining healthy cells will die off and insulin dosages will need to be increased. A number of research projects are underway to preserve the function of existing beta cells past the Honeymoon Phase.

Managing T1D

It's a big change, but people with T1D can live long, full and happy lives.

Life with T1D can be long and happy with the right management.  Advances in medication and technology make life easier, safer and better.
Treating T1D means replacing the insulin that your pancreas doesn’t make and monitoring your blood glucose levels.


People with T1D work closely with their medical team to find the right insulin treatment for them. Insulin can be delivered via syringes or pens, pumps or the new artificial pancreas systems.

The majority of people who are injecting insulin follow a basal-bolus regime. A basal-bolus regime involves taking a long-acting form of insulin once or twice a day to keep BGLs stable when you are not eating. This is known as the ‘basal’ injection. It also includes taking a rapid-acting insulin before each meal to prevent rises in blood glucose levels resulting from eating carbohydrates or to correct elevated blood glucose levels between meals. This is known as the ‘bolus’ injection. One of the main advantages of a basal-bolus regimen is that it attempts to mimic how the body releases insulin in people who do not have T1D It also allows for flexibility around what is eaten and when. However, it usually involves taking between four and eight injections a day.

There are five main types of insulin available in Australia. Each type differs with respect to how quickly it begins to act and how long its effect persists. Most people with type 1 diabetes need to use more than one kind of insulin preparation to mimic the role of the pancreas as closely as possible. 

  • Rapid acting insulin analogues 
  • Short acting insulin
  • Intermediate acting insulin
  • Long acting insulin analogues 
  • Pre-mixed insulin

No single regimen, or combination of insulin, works well for everyone. The type of insulin, how much is used and how often will depend on the individual. The right insulin regimen for you is the one that helps maintain your blood glucose level as close to normal as possible without hypoglycaemia.

Blood Glucose Levels

Before you developed type 1 diabetes your pancreas would produce a low level of insulin across the day to help move glucose from your bloodstream into the various cells of your body to provide them with energy. When you ate, your blood glucose level (BGL) would rise and your pancreas would respond by producing a surge of insulin. This would help move excess glucose into your muscles and liver to be stored as glycogen. If your BGL dropped during the day, this glycogen would be broken down and released back into the blood stream as glucose. By constantly sensing how much glucose is in the bloodstream and adjusting how much insulin it secreted, your pancreas kept your BGL between 4 and 8 mmol/L at all times. With T1D you need to manage this process manually by checking your BGL  and adding insulin into your body. Ideally you should aim to do at least four blood glucose checks a day. There are two devices to do this: Constant Glucose Monitor (CGM) or a Blood Glucose Meter.

In addition to monitoring your BGLs at home, your doctor or diabetes team will arrange for you to have a special blood test, known as a haemoglobin A1c (HbA1c) every three months. 

Living with diabetes can be incredibly frustrating. Over the course of a couple of days you eat the same amount of food, take the same amount of insulin and do the same amount of exercise, but your blood glucose levels from day to day can be completely different. Keeping your blood glucose levels within target sounds easy. Even with your best efforts, trying to keep your blood glucose level within range all the time is impossible. But its important to try and manage the fluctuations as best you can. 

Complications can be reduced by up to 76% with tight glucose management.

Targets and Checkups

  • Blood Glucose:

    • When you wake up: 4 to 7 mmol/L
    • Before meals: 4 to 7 mmol/L
    • 2 hours after meals: 5 to 10 mmol/L
    • Before exercise: greater than 5 mmol/L and less than 15 mmol/L
    • Before you go to bed: 6 to 10 mmol/L
  • HbA1c as close to 7% or (53 mmol/ mol) as possible

  • Blood pressure reading 130/80 mmHg or lower

  • The target for total cholesterol is 4 mmol/L, with target LDL (bad) cholesterol of <2 mmol/L; HDL (good) cholesterol > 1mmol/L and triglycerides of < 1.8 mmol/L.

Endocrinologist – it is important to have a good working relationship with your Endocrinologist with regular checkups.

Regular tests:

  • HbA1c – immediately and then every 3 months
  • Blood pressure – every doctor’s visit
  • Cholesterol – every year
  • Eyes (ophthalmologist) – every one to two years
  • Feet – every year
  • Kidneys – every year
  • Teeth and gums – regularly
  • Thyroid – immediately and then every 3 months

Medicare will cover the costs of five visits a year to allied health professionals (like dieticians and podiatrists).

T1D can sometimes be incredibly hard and frustrating. If you’d like to talk please contact:

Medicare also provide rebates for psychological services when referred by your GP under a Mental Health Care Plan (MHCP).

More About Type 1 Diabetes

About T1D
Insulin Pump Program
Children with T1D
T1D Directory
Adult Guide

Latest About JDRF & Type 1 Diabetes