The high prevalence of excess weight represents a significant challenge to public health in Australia. Understanding the current rate provides a measure of the population’s health status and guides the allocation of resources toward prevention and management. The statistics reveal a broad trend affecting millions of Australians, making data collection and analysis fundamental for national health authorities.
Defining and Measuring Obesity in Australia
Australian health authorities, including the Australian Institute of Health and Welfare (AIHW) and the Australian Bureau of Statistics (ABS), primarily use Body Mass Index (BMI) to categorize population weight status. BMI is an internationally recognized standard calculated by dividing a person’s weight in kilograms by the square of their height in meters. For adults, a BMI of 25.0 to 29.9 kg/m² is classified as overweight, while a BMI of 30.0 kg/m² or higher is defined as obesity.
BMI is a practical, population-level tool for identifying excess body weight, though it does not account for differences in body composition like muscle mass. For children and adolescents, the calculation is more complex, relying on age- and sex-specific cut-off points to account for growth and development. National prevalence figures are typically sourced from the ABS National Health Survey, which often includes measured height and weight data for greater accuracy.
Current National Prevalence and Recent Trends
The most current national data shows that two-thirds of Australian adults are living with excess weight. In 2022–2023, 65.8% of adults aged 18 and over were classified as either overweight or obese, with the adult obesity rate standing at 31.7%. This represents a significant increase over the past two decades.
The prevalence of overweight and obesity in adults has steadily risen from 56% in 1995. This trend is driven by the increase in the number of people classified as obese, which rose from 19% in 1995 to 32% in 2022. The proportion of adults with severe obesity (BMI of 40 or more) more than doubled between 2007–2008 and 2022–2023, rising from 2.2% to 4.6%.
For the younger population, the rate of excess weight remains high. In 2022, 26% of children and adolescents aged 2–17 were living with overweight or obesity, with 8.1% specifically classified as having obesity. The combined rate for children has increased from 20% in 1995, indicating a long-term upward trend that has stabilized in recent years.
Variations Across Australian Demographics
The burden of excess weight varies significantly across different demographic groups in Australia. Geographic location is a strong indicator, as prevalence is higher outside of major metropolitan areas. In 2022, 70% of adults in outer regional and remote areas were living with excess weight, compared to 64% in major cities.
Socio-economic status (SES) also shows a clear gradient, with lower SES areas reporting higher rates. Adults residing in the lowest socioeconomic areas have a combined overweight and obesity prevalence of 68%, which is significantly higher than the 60% recorded for those in the highest socioeconomic areas. This difference highlights a persistent health inequality tied to disadvantage.
The rates also vary by age and gender, generally increasing as people get older. The proportion of men living with overweight or obesity reaches a peak of 81% in the 65 to 74 age group. While men have a higher overall rate of combined overweight and obesity than women (71% versus 61%), the prevalence of solely having obesity is statistically similar between the sexes, at 33% for men and 31% for women.
Key Societal Drivers of Weight Gain
The high rates of excess weight in Australia are closely linked to the pervasive influence of the modern environment, which promotes energy imbalance. This imbalance occurs when energy consumed consistently exceeds the energy expended through physical activity. This situation is exacerbated by the contemporary food environment, which makes high-energy, low-nutrient foods widely accessible and often more affordable than fresh produce.
The widespread availability of convenience foods, along with increasing portion sizes in the commercial food sector, contributes significantly to higher caloric intake across the population. Many Australians also experience a reduction in daily physical activity due to increasingly sedentary occupations and reliance on motorized transport. This shift has been compounded by changes in urban design that often prioritize vehicles over pedestrian and cycling infrastructure, reducing opportunities for incidental activity.
The concept of an “obesogenic environment” describes the complex interplay of social, environmental, and commercial determinants that influence body weight. Structural factors, such as time pressures, inadequate sleep, and the commercial marketing of unhealthy foods, make healthy lifestyle choices more difficult. These drivers create a systemic challenge that goes beyond individual choices, favoring weight gain.