Glucose builds up in the blood leading to high blood glucose levels which cause the health problems linked to diabetes.

You can have diabetes and have no symptoms. If they do occur, the most common symptoms are:

• feeling very thirsty
• urinating frequently, particularly at night
• feeling very tired
• weight loss and loss of muscle bulk

Check your symptoms with healthdirect’s Symptom Checker to get advice on when to seek medical attention, or if you are concerned you may have diabetes see your doctor.

Are you at risk?

Find out if you're at risk of heart disease, type 2 diabetes or kidney disease using our Risk Checker.

What causes diabetes?

The amount of sugar in the blood is usually controlled by a hormone called 'insulin', which is produced by the pancreas (a gland behind the stomach).

When food is digested and enters your bloodstream, insulin moves glucose out of the blood and into cells, where it is broken down to produce energy.

However, if you have diabetes, your body cannot break down glucose into energy. This is because there is either not enough insulin to move the glucose, or the insulin produced does not work properly. Glucose builds up in the blood resulting in high blood glucose levels.

Diabetes types

There are three main types of diabetes:

Diabetes type 1

Type 1 diabetes is an auto-immune disease where the body's immune system attacks the insulin-producing cells of the pancreas. People with type 1 diabetes cannot produce insulin and require lifelong insulin replacement for survival.

The disease can occur at any age, although it mostly occurs in children and young adults. Type 1 diabetes is sometimes referred to as 'juvenile onset diabetes' or 'insulin dependent diabetes'.

Diabetes type 2

Type 2 diabetes is associated with hereditary factors and lifestyle risk factors including poor diet, insufficient physical activity and being overweight or obese.

People with type 2 diabetes may be able to manage their condition through lifestyle changes; however, diabetes medications or insulin replacement may also be required to control blood sugar levels.

Type 2 diabetes occurs mostly in people aged over 40 years old; however, the disease is also becoming increasingly prevalent in younger age groups.

Gestational diabetes

Gestational diabetes occurs during pregnancy. The condition usually disappears once the baby is born; however, a history of gestational diabetes increases a woman's risk of developing type 2 diabetes later in life.

The condition may be managed through adopting healthy dietary and exercise habits, although diabetes medication, including insulin, may also be required to manage blood sugar levels.

For more information on pre-existing diabetes and pregnancy and gestational diabetes, visit Pregnancy, Birth and Baby website.

Monitoring

While the majority of people with diabetes do not need finger prick monitoring, those taking insulin or in other special circumstances may need to do so.

The Australian College of Nursing recommends people with diabetes who need to monitor their glucose levels self-manage their own blood glucose monitoring whenever possible.

For more information, speak to your doctor or visit the Choosing Wisely Australia website.

More information

Diabetes Australia provides more information on diabetes on its website. You can also call the National Diabetes Services Scheme (NDSS) on 1800 637 700.

If you are concerned you may have diabetes please see your doctor.