Healthy Weight


Cancer Council Australia Position Statement on Overweight, Obesity and Cancer Prevention 

Shape Up Australia

Health risks

Being overweight or obese is a risk factor for cancer of the bowel, kidney, pancreas, oesophagus and endometrium (womb), as well as breast cancer in post-menopausal women.

The levels of overweight and obesity are steadily increasing in Australia.  According to the Australian Bureau of Statistics in 2011-2012 63.4% of Australian adults were overweight and obese and 25.3% of children (aged 5-17).

Are you overweight or obese?

Being overweight is having a Body Mass Index (BMI) over 25, or a waist measurement over 80cm for women or 94cm for men. Use a tape measure to find out your waist measurement (at the navel for men, and around the narrowest point for women).  Being obese is having a BMI of over 30.

What’s your Body Mass Index (BMI)?

Your BMI is a measure of your weight for height. Calculate your BMI by dividing your weight in kilograms by your height in metres-squared (see the table below).

How to Calculate Your Body Mass Index (BMI)

1.  Find out your height in metres and weight in kilograms.

2.    Multiply your height by your height.

3.  Divide your weight by this number.  This is your BMI.


1.  Mary is 1.7m (170cm) tall and weighs 70kg

2.   1.7 X  1.7 =  2.89

3.   70 ÷2.89 = 24.2

Mary’s BMI is 24.2 putting her in the ‘healthy weight’ category (see below)


Underweight (BMI under 18.5) 

This BMI is under the optimum weight for height. You could probably afford to gain a little weight, but you should discuss this with your GP first.

This is a normal situation if you eat a healthy diet, and are active and energetic. However, being underweight can also be a sign of a problem and often occurs during treatment for cancer. You should talk to your GP to investigate this fully.

Healthy weight (BMI between 18.5 and 24.9) 

This BMI range is a healthy weight for height. Eating a balanced eating pattern and leading a physically active lifestyle can help maintain a healthy weight.

Overweight (BMI 25 and over) 

This BMI range is over the optimum weight for height. Being overweight is a risk factor for many health problems. Since BMI does not directly measure body fat, it is possible to be overweight but not obese. If you are concerned about being overweight you should talk to your GP or dietitian first.

Obese (BMI of 30 and over) 

This BMI range is over the optimum weight for height. Obesity is a risk factor for some cancers and other health problems like heart disease, so talk to your GP or dietitian to help you achieve a healthier weight.

Diets are not the answer to healthy weight loss
Diets generally do not work. Strict diets usually result in weight regain because you cannot keep them going. It is far better to make moderate changes that will last you for a lifetime.  Be realistic about the changes you make and do it gradually so you can stick to the improvements you make. You can still enjoy the treats you love occasionally. But keeping to a healthy eating plan most of the time will help you to look and feel good.