Pre-diabetes is a condition which signals that the body has stopped processing blood glucose well. Diabetes Australia estimates that two million Australians have pre-diabetes, and that each year around 5–10% of them develop type 2 diabetes, a condition whose complications include heart, kidney and eye disease.

One of the risk factors for the development of pre-diabetes is being at an unhealthy weight; in 2017–18 the Australian Institute of Health and Welfare (AIHW) estimated that 67% of Australian adults were within an unhealthy weight range.

In this article, we will look further into the connection between living in a larger body size and pre-diabetes. Then we’ll see how the onset of type 2 diabetes can be delayed or prevented by adopting a healthier lifestyle.

Pre-diabetes—your chance to prevent type 2 diabetes

The exact cause of pre-diabetes is unknown, but its risk factors are similar to those for type 2 diabetes. As well as being at an unhealthy weight, they include not doing the recommended amount of exercise, having high cholesterol and high blood pressure and smoking.

Before a person is diagnosed with pre-diabetes, changes in the body that are associated with the condition may already have occurred. One significant change is the development of insulin resistance.

Insulin is a hormone that is produced by the pancreas. It enables glucose in the blood to move into cells in muscles where it’s used for energy. This process regulates the level of blood glucose. Insulin resistance occurs when the muscles and liver do not respond effectively to the hormone. The body starts to produce more insulin in an attempt to stabilise glucose levels, and keeps doing so until the pancreas is exhausted, resulting in too much glucose circulating in the blood.

Being at an unhealthy weight can make your body resistant to insulin.

As there are no reliable signs or symptoms of pre-diabetes, it is usually diagnosed when a person’s doctor is concerned that they may have elevated blood glucose and sends them for a blood test. There are several tests to confirm pre-diabetes:  

  •   Fasting blood glucose test (FBGT): a blood sample is taken to show the level of glucose in your blood. This is done as a fasting blood test (after 8–10 hours of not eating and only
    drinking water).
  •     Glucose tolerance test (GTT): If your fasting blood glucose test is high, your GP may arrange for you to have a GTT. This test looks at both a fasting reading and then at a one- and two-hour reading, after a glucose drink, to see your body’s response. This will take up to three hours.
  •     Hba1c: This non-fasting test can be taken at any time. It shows the average of your blood glucose level over a period of three months.

There are two types of pre-diabetes, impaired glucose tolerance (IGT) and impaired fasting glucose (IFG). Both involve increased blood glucose levels.

Unhealthy weight and pre-diabetes and your diabetes risk

In Australia, a person is said to be at an unhealthy weight if their body mass index (BMI) is equal to or greater than 30. This is a simple calculation of weight divided by height squared.

Being at an unhealthy weight is one of the most important risk factors in the development of pre-diabetes and type 2 diabetes. This is because, as mentioned previously, it can make the body resistant to insulin. It also puts you at risk of other health conditions, including high blood pressure, heart disease and some types of cancer.

Risk factors for developing pre-diabetes in people who are at an unhealthy body weight

Being at an unhealthy body weight is linked to the following risk factors for pre-diabetes:

  • Having high blood pressure
  • Having high cholesterol
  • Eating an unhealthy diet.

Prevention of unhealthy body weight and pre-diabetes

People who are at an unhealthy body weight can prevent the onset of pre-diabetes by:

  • reaching and maintaining a healthy weight
  • eating a healthy diet
  • doing the recommended amount of exercise
  • quitting smoking (if relevant)
  • limiting alcohol consumption (if relevant)
  • having regular check-ups with their healthcare provider.

Remember, it’s always best to consult with a healthcare provider before starting any new diet or exercise program.

Will losing weight help with pre-diabetes?

Having pre-diabetes does not mean that you’ll automatically develop type 2 diabetes. Reaching and maintaining a healthy weight helps the insulin in your body work better and lowers your blood glucose levels. If you have excess body fat, particularly around your middle, losing just 5% of your body weight can significantly reduce the risk of type 2 diabetes. To keep your weight in a healthy range, focus on making small and realistic changes to your lifestyle to improve your diet and increase your physical activity. It is better to start with any goal than to try and be perfect right away. 

Diet and the management of pre-diabetes

For people who are living with pre-diabetes, a nutritious diet will help to keep their blood glucose levels within a healthy range and help with the maintenance of a healthy weight. The Australian Dietary Guidelines and the Australian Guide to Healthy Eating provide information and advice about what a healthy diet is.

One of the Australian Dietary Guidelines is: “Enjoy a wide variety of nutritious foods from the five food groups every day. And drink plenty of water”.

The five food groups mentioned are:

1. Vegetables and legumes/beans

  1. Fruit
  2. Grain and cereal foods, aiming for mostly wholegrains, low-GI and/or high-fibre varieties.
  3. Lean meat and poultry, fish, eggs, tofu, nuts, seeds, legumes and beans.
  4. Milk, yoghurt, cheese and/or alternatives, aiming for mostly reduced fat and fortified alternatives.

The Australian Guide to Healthy Eating shows the proportions of the five food groups we should eat every day.

People who are living with pre-diabetes should eat a wide range of foods from these groups that are high in fibre and low in the glycaemic index (GI). The glycaemic index shows how quickly the carbohydrates in a food are broken down and absorbed into the bloodstream. Foods with a high GI cause a rapid rise in blood glucose levels, which can lead to increased insulin release from the pancreas and may promote more cravings and overeating. Foods with a low GI result in a slower rise.

Foods that are high in fibre can also help regulate blood glucose levels by slowing down the absorption of glucose into the bloodstream. According to the Australian Government’s Health Direct website, foods that are both low GI and high in fibre include:

  •       oats (rolled, steel-cut or oat bran)
  •       grains (for example, pasta, rice, noodles, quinoa, barley)
  •       legumes (for example, lentils, split peas and chickpeas)
  •       most types of fruit.

Here are some recipes that can help manage pre-diabetes.

Exercise and the management of pre-diabetes

Regular exercise can improve insulin sensitivity, reduce blood glucose levels and enhance mobility and mental wellbeing. It can also help maintain a healthy weight, lower blood pressure and reduce the risk of heart disease. 

Australian Government guidelines recommend that adults do at least 30 minutes of moderate-intensity physical activity most days. Moderate-intensity exercise is any activity that causes your heart to beat faster and makes you breathe harder. Examples are:

  •       cycling
  •       brisk walking
  •       tennis. 

As an alternative, you could do three short bursts of 10–15 minutes of activity, which provide similar benefits in a time-efficient way. If you are just starting out with exercising, light-intensity activities are also very beneficial and can help manage your blood glucose levels. Light-intensity activities include walking at a normal pace, dancing and gentle Tai Chi.

Resistance training also supports weight management by improving the body’s muscle mass and increasing the metabolism. Resistance training is any activity that makes your muscles work harder than usual, increasing their strength, size, power and endurance. Examples include lifting free weights and using weight machines or resistance bands.


To help manage pre-diabetes and potentially prevent type 2 diabetes, it is recommended that a person reaches and/or maintains a healthy weight. Strategies to help achieve this include doing regular exercise and eating a variety of healthy nutritious foods.

The Life! program is a free healthy lifestyle program that helps you improve your eating habits, increase your physical activity and pre-diabetes prevention and manage stress. You can choose from a group course or our telephone health coaching service.

Our experienced health professionals will help you make changes to your lifestyle so that you can successfully manage pre-diabetes.

Since 2007, over 75,000 Victorians have learnt more about living a healthy life with the Life! program. It is the largest prevention program of its kind in Australia.

Life! is funded by the Victorian government and managed by Diabetes Victoria.

You can take a quick online health test and check your eligibility for the program here


Diabetes – Pre-diabetes – Better Health Channel
Pre-diabetes – Diabetes Australia
Dietary and nutritional approaches for prevention and management of type 2 diabetes – The BMJ
High-fibre foods and diet – healthdirect
What To Do If You Have Pre-diabetes – The Life! Program
Overweight and obesity – Australian Government Department of Health and Aged Care