What is type 2 diabetes?

Type 2 diabetes is a chronic disease. It occurs when your body cannot make enough insulin – the hormone that controls the amount of glucose in your blood – and cannot use the insulin it does make effectively1. This is called insulin resistance, and it develops over months, or even years.

Diagnosed early, type 2 diabetes can be controlled with diet and exercise. If diet and exercise alone are not enough to control your glucose levels, you may also need to take medication.

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 about insulin therapy for type 2 diabetes

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 cause serious health complications, such as heart disease and stroke, kidney and eye diseases, and nerve damage.

High blood glucose can also interfere with the insulin-producing beta cells in your pancreas, making them less able to produce the hormone.
Explore the link between blood glucose, insulin and HbA1C

What causes type 2 diabetes?

The causes of type 2 diabetes are not fully understood, but it is strongly linked with being overweight or obese, as well as with family history and ethnicity2. While genes have a role to play, your lifestyle choices are also very important. A healthy diet and regular exercise will reduce your chances of developing type 2 diabetes – even if the disease runs in your family.

What causes type 2 diabetes?

What are the symptoms of type 2 diabetes?

Being middle aged or older, being overweight, or having a family history of type 2 diabetes all increase your risk of developing the disease. Type 2 diabetes develops gradually, so you may not even notice the symptoms until they become obvious. This is dangerous, as high blood glucose levels may already be damaging your body.

If you think you may be at risk, get screened for diabetes if you notice any of these signs:


  • Excessive urination: as your body expels excess glucose
  • Extreme thirst: resulting from urination
  • 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)
  • Weight loss: as your body uses fat for energy when cells cannot absorb glucose

Diagnosing type 2 diabetes

The initial test for diabetes is a fasting (nothing to eat or drink for 8 hours) blood glucose test. An HbA1C test may also be taken. This will measure your average blood glucose levels over the past two to three months, and does not require fasting.

If your glucose levels are above normal, but do not confirm diabetes, a glucose tolerance test may be taken. Your fasting blood glucose level will be measured, after which you will consume a sugary drink and have your levels measured again two hours later.

Normal blood glucose levels and levels that indicate type 2 diabetes and 'prediabetes' (elevated levels indicating that you are at risk of progressing to type 2 diabetes) are compared below.


I've been diagnosed with type 2 diabetes - what now?

I've been diagnosed with type 2 diabetes – what now?

This will depend on what stage of type 2 diabetes you have. In the early stages, or with prediabetes, you may be able to control your blood glucose with a healthier diet and more exercise. However, type 2 diabetes is a progressive disease, so most people will need to move on to another treatment at some point to keep their glucose levels in a healthy range.

Being diagnosed with type 2 diabetes may seem overwhelming, but remember that diagnosis is the first step to getting your health under control and avoiding serious complications. Take charge of the situation by learning as much as you can about the disease and its management.


Type 2 diabetes and cardiovascular risk

Did you know that having type 2 diabetes also increases your risk of developing cardiovascular problems – including heart attack and stroke? This is why it's important that you take care of your heart health and type 2 diabetes together. Good type 2 diabetes management can reduce your risk of heart disease, so find out more about the steps you can take to get in control of both.

Learn how to lower your cardiovascular risk

Treating type 2 diabetes

Type 2 diabetes is a progressive disease, so you will probably adjust the way you manage it as you get older. There is a broad range of treatment options available to help you keep your blood glucose under control, including lifestyle changes, oral medications and insulin therapy.

Explore type 2 diabetes treatments

Living with type 2 diabetes

A type 2 diagnosis doesn't mean you should expect less out of life. But you will need to learn how to manage your blood glucose for different situations and activities so that you stay healthy and active. We have lots of information and resources to help you get started.

Get tips for living well with type 2 diabetes

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