This report highlights the significant public health issue of overweight and obesity impacting the health of the ACT community. This, along with the report describing the burden of disease in the ACT, are the first since the ending of the COVID-19 public health emergency declaration in the ACT. The main purpose of these reports is to refocus our attention on key public health issues impacting on the health and well-being of our community at this time.
This information seeks to inform future policy, planning and research, developed both within Government and by external stakeholders.
Overweight and obesity is a complex health condition which often start early in life and is influenced by factors both within and beyond a person’s control.
Overweight and obesity is the second leading cause of disease burden in Australia through increased risk of chronic diseases such as cardiovascular disease, type 2 diabetes and some cancers. It has been estimated that maternal overweight and obesity contributes to a significant proportion of adverse pregnancy outcomes in the ACT.
Supporting our population in achieving and maintaining a healthy body weight is therefore important to assist Canberrans to live longer and healthier lives.
In 2021, nearly 2 in 3 Canberran adults and 1 in 3 Canberran children reported being overweight or obese.
Of particular concern is the data showing that obesity levels are increasing in adults and children of kindergarten age. Similarly, the proportion of ACT mothers living with overweight or obesity in their first trimester of pregnancy has increased over the last ten years.
The ACT Personality and Total Health Through Life Study (PATH study) is also showing us that there is a generational increase in overweight and obesity in the ACT – younger people are experiencing more overweight and obesity than previous generations did at the same age.
We are not alone in this challenge, with similar levels and trends seen across Australia and around the world.
There is some promising data, which we must look at more closely and learn from.
Amongst our year 6 students there is an encouraging downward trend in overweight and obesity between 2006 and 2018, and we look forward to the analysis of 2021/22 data to see if this trend continues.
The impacts of overweight and obesity on individuals, our families, community and health systems are such that it is critical that there continues to be a strong focus on how we can turn things around.
The focus of our efforts must continue to support individuals living with overweight and obesity and prioritise prevention at all stages of life. The complexity of this issue is acknowledged, including the importance of encouraging a positive self‑image whilst promoting positive health changes across the community and specifically in support of people living with overweight and obesity.
This requires all of us to play our part; individuals, community, government and non-government partners, across health, education, environment, business and economic sectors.
The ACT Government's Healthy Canberra ACT Preventive Health Plan 2020-2025 and the supporting First Three Year Action Plan (2020-2022) seek to articulate areas for government-led action in a wide range of areas, delivered in partnership with a range of stakeholders. In anticipation of the development of a Second Action Plan, I would encourage everyone to consider how the impacts of overweight and obesity could be mitigated.
This report provides a snapshot of a priority population health issue in the ACT. Statistics on a broad range of population health topics are published and regularly updated on the HealthStats ACT website.
Differences in statistical methods and calculations, data updates and guidelines may result in the information contained in this report varying from previously published information.
COVID-19 has impacted the ability of direct data collection for some of the key statistics, including interruptions to national survey data collection leading to limitations around the availability of up-to-date data for these indicators. This is important to consider when considering the information discussed in this report.
Weight status as a population health measure
Weight status, including the proportion of overweight and obesity among ACT adults, children and adolescents, is primarily determined using population health surveys. These provide a snapshot of body weight at key points in life and can show changes over time at the population level.
The principle national survey for objective data on overweight and obesity is the National Health Survey (NHS) by the Australian Bureau of Statistics (ABS). This data was not collected during the 2020-21 survey due to safety concerns during the COVID-19 pandemic. This report utilises data from the ABS NHS 2018, the most recent comprehensive data on weight status of Australians.
Key data sources that report weight status in the ACT include:
ACT General Health Survey of adults and children
ACT Kindergarten Health Check of children in their first year of primary school
ACT Personality and Total Health Through Life Study (PATH)
ACT Maternal and Perinatal Data Collection
ACT Physical Activity and Nutrition Survey (ACTPANS) of Year 6 primary school students.
Further information about these data sources, including methodology and frequency, is available here. ACT’s indicators for weight status are available at HealthStats.
Measurement of weight status in the population
The measurement and definition of healthy weight is challenging for individual and population health assessment purposes.
Body mass index (BMI) and waist circumference are measurements that are commonly used in the assessment of healthy weight.
Body Mass Index (BMI)
The most commonly used measure of healthy weight is the BMI. This measurement takes into account an individual’s weight and height.
The World Health Organization (WHO) defines a BMI of between 18.50 and 24.99 as a healthy weight range for adults.
For children, the healthy weight range for BMI is categorised using age specific ranges developed by the International Obesity Taskforce.
WhileBMI in not always an accurate measure of healthy weight for an individual, the WHO and the World Obesity Federation recommend BMI as the best measure of weight status for a population.
Waist circumference is an alternate measure of risk associated with excess weight and is based on evidence that carrying excess weight around the waist is more of a health risk than if it were on the hips and thighs, regardless of a person’s height or build.
Waist measurements higher than 94cm for men or 80cm for women are linked to increased risk of developing chronic diseases.
Waist circumference measurements do not apply to children, pregnant women or people with certain medical conditions and backgrounds which change their body shape.
Population surveys collect data on these measures either objectively through direct physical measurement or by participant self-report.
The Australian Bureau of Statistics identifies that while self-reported measures are logistically simpler to collect, it is less accurate because of the tendency for people to under-report weight and over-report height.
The ACT General Health Survey and Physical Activity and Nutrition Survey self collect data through self-report.
Maintaining a healthy body weight is important to support longer and healthier lives.
In 2021, 36.1% of ACT adults reported having a healthy weight (33.5% of males and 38.7% of females), while 59.6% of ACT children were classified as having a healthy weight.
A national perspective is provided by the 2018 National Health Survey which found that 35.1% of ACT adults reported having a healthy weight compared to 31.7% of Australian adults.
Overweight and obesity
Overweight and obesity is defined as carrying excess body fat that presents health risks.
Overweight is defined as a BMI between 25.00 and 29.99. Obesity is defined as a BMI of 30.00 or higher.
In 2021, 62.2.% of adult Canberrans reported being either overweight (35.5%) or obese (26.7%) in the ACT General Health Survey.
The more excess weight a person carries, the higher their risk of developing health and wellbeing issues. This means living with obesity puts a person at greater risk of health conditions than living with overweight.
People living with obesity have a life expectancy that is reduced by 2 to 10 years, which is similar to the impact of smoking.
Overweight and obesity is a major risk factor for:
The proportion of the population reported as overweight or obese continues to increase from childhood through to at least 65 years of age.
There is also a generational increase in overweight and obesity. The PATH Study follows individuals as they age, providing insight into the future trajectory of overweight and obesity in the ACT. This is showing us that younger people in the ACT are experiencing more overweight and obesity than previous generations did at the same age. People are living with overweight and obesity at younger ages.
The prevalence of overweight and obesity is discussed further in the next section.
Burden of disease
Burden of disease studies look at the combined impact of dying early and living with disease or injury.
Overweight and obesity are a leading contributor to the total burden of disease in Australia.