top of page

How common is overweight and obesity in Australia?



  • In 2017–18, an estimated 2 in 3 (67%) Australians aged 18 and over were overweight or obese (36% were overweight but not obese, and 31% were obese). That’s around 12.5 million adults.

  • More men than women were overweight but not obese (42% of men and 30% of women), but obesity rates for men and women were similar (33% of men and 30% of women).

  • Obesity is more common in older age groups—16% of adults aged 18–24 were obese, compared with 41% of adults aged 65–74.

  • The proportion of adults with a waist circumference associated with a substantially increased risk of metabolic complications increased with age, and was higher in women than men (peaking at 57% of men aged 65–74, and 65% of women aged 75–84) (ABS 2018).


Children and adolescents

In 2017–18, an estimated 1 in 4 (25%) children and adolescents aged 2–17 were overweight or obese (1.2 million children and adolescents). Of all children and adolescents aged 2–17, 17% were overweight but not obese, and 8.2% were obese. Rates varied across age groups, but were similar for males and females (ABS 2018).

Children are more likely to pick up and develop unhealthy habits from people with key influences in their lives, such as parents/guardians. This means parents/guardians inadvertently jeopardize their children's health when they live an unhealthy lifestyle as they are likely to pass on unhealthy habits to their children, which increases the likelihood they will become overweight or obese.


​The financial burden of obesity in Australia is currently estimated to be $11.8 billion annually. Those figures consist of $5.4 billion in direct health costs and $6.4 billion in indirect costs. That’s costing EVERY Australian approximately $472 per year, with the figure rapidly growing.

As the rate of overweight and obesity increases, so too does the financial cost. Reports indicate if no further action is taken to slow the growth of obesity then there will be 2.4 million more obese people in 2025 than in 2011-12 and $87.7 billion in additional costs due to obesity to society over the ten years (2015-16 to 2024-25). There will also be a higher proportion of obesity class III, meaning higher health risks and costs.

By investing in selected interventions to curb obesity, Australians can save around $2.1 billion between 2015-2025. The World Health Organization (WHO) target is to halt the growth in obesity, return to and maintain the 2010 obesity prevalence levels. It is estimated that the obesity prevalence rate in 2010 was 26 percent. If Australia were to have a prevalence rate of 26 percent prevalence in 2025, that would mean 1.6 million fewer obese people and an estimated ten year cumulative benefit of $10.3 billion by 2025.


What about the WORLDWIDE statistics?


  • Worldwide obesity has nearly tripled since 1975.

  • In 2016, more than 1.9 billion adults, aged 18 years and older, were overweight. Of these over 650 million were obese.

  • 39% of adults aged 18 years and over were overweight in 2016, and 13% were obese.

  • Most of the world's population live in countries where overweight and obesity kills more people than underweight.

  • Globally there are more people who are obese than underweight – this occurs in every region except parts of sub-Saharan Africa and Asia.

  • 38 million children under the age of 5 were overweight or obese in 2019.

  • Over 340 million children and adolescents aged 5-19 were overweight or obese in 2016.

  • Obesity is preventable.




What does obesity and overweight mean?

​Overweight and obesity are defined as abnormal or excessive fat accumulation that increases the risk of health problems, diseases, chronic conditions, and is associated with higher rates of death. It mainly occurs because of an imbalance between energy intake (from the diet) and energy expenditure (through physical activities and bodily functions).


Body mass index (BMI) is a simple index of weight-for-height that is commonly used to classify overweight and obesity in adults. It is defined as a person's weight in kilograms divided by the square of their height in meters (kg/m2).

For adults, the World Health Organization (WHO) defines overweight and obesity as follows:

  • overweight is a BMI greater than or equal to 25; and
  • obesity is a BMI greater than or equal to 30.

BMI provides the most useful population-level measure of overweight and obesity as it is the same for both sexes and for all ages of adults. However, it should be considered a rough guide as it doesn’t measure what the weight is actually comprised of (body composition). For example, body builders may fall into the ‘overweight’ category due to the weight of their muscles.

What causes obesity and overweight?


The fundamental cause of obesity and overweight is an energy imbalance between calories consumed and calories expended. Globally, there has been:

  • an increased intake of energy-dense foods that are high in fat and sugars; and

  • an increase in physical inactivity due to the increasingly sedentary nature of many forms of work, changing modes of transportation, and increasing urbanization.


Changes in dietary and physical activity patterns are often the result of environmental and societal changes associated with development and lack of supportive policies in sectors such as health, agriculture, transport, urban planning, environment, food processing, distribution, marketing, and education.


What are common health consequences of being overweight or obese?



Being overweight or obese increases the likelihood of developing many health problems and the risk of incurring these health problems increases with increases in BMI. Some of these health problems include:

  • Cardiovascular diseases (mainly heart disease and stroke), which were the leading cause of death in 2012;

  • Asthma

  • Back problems

  • Pain in the back or joints

  • Type 2 diabetes;

  • musculoskeletal disorders (especially osteoarthritis – a highly disabling degenerative disease of the joints);

  • Some cancers (including endometrial, breast, ovarian, prostate, liver, gallbladder, kidney, and colon).

  • Chronic kidney disease

  • Fatigue

We often pass on our habits and traits to our children so when we live an unhealthy lifestyle, our children are likely to follow down the same path. Childhood obesity is associated with a higher chance of obesity, premature death and disability in adulthood. But in addition to increased future risks, obese children experience breathing difficulties, increased risk of fractures, hypertension, early markers of cardiovascular disease, insulin resistance and psychological effects including depression. No parent wants their children to suffer so it is important to get help and create a healthier lifestyle for you, your family, and the wider community.

overweight consequences



Australian Institute of Health and Welfare, Australian Government, Overweight and Obesity (23 July 2020)

PwC Australia, Weighing the cost of obesity: A case for action (October 2015)


World Health Organization, Obesity and Overweight (1 April 2020)


Bupa, New statistics: Australia’s obesity epidemic reaches crisis point (27 March 2019)

The obesity Collective, Weighing in: Australia’s growing obesity epidemic report (2019)



bottom of page