Overweight and obesity
Overweight and obesity refers to excess body weight. Excess weight, especially obesity, increases a person’s risk of developing chronic kidney disease (CKD) by raising levels of blood pressure and abnormal blood abnormal blood lipids, and placing people at increased risk of cardiovascular disease and type 2 diabetes (NHMRC 2013).
Being overweight or obese can make it more difficult to control or manage chronic diseases. Overweight and obesity is also associated with higher rates of death (AIHW 2023, 2021). Evidence has shown that the risk of CKD is almost 1.5 times as high for an overweight but not obese person and almost twice as high for an obese person. Obese women have a higher risk of developing CKD than obese men (Wang et al. 2008).
In adults, overweight and obesity is defined as a body mass index (BMI) of 25–29 kg/m2 and ≥30 kg/m2, respectively.
This report uses BMI to define overweight and obesity. For information on waist circumference, see 'Waist circumference' in Diabetes: Australian facts.
Based on measured BMI from the Australian Bureau of Statistics (ABS) 2022 National Health Survey:
- one in 4 children and adolescents aged 2–17 (26%) were living with overweight or obesity. This is approximately 1.3 million children and adolescents. The proportion living with overweight or obesity was similar for boys and girls across most age groups, except for the youngest age group, where more girls aged 2–4 (24%) were living with overweight or obesity than boys (14%).
- 66% of adults aged 18 and over were living with overweight or obesity, with 34% living with overweight but not obesity, and 32% living with obesity.
- men had higher rates of overweight or obesity than women (71% men, 61% women), and higher rates of obesity (33% men, 31% women).
- obesity was more common among older age groups – 15% of men and 16% of women aged 18–24 years were living with obesity, compared with 41% of men and 37% of women aged 65–74 (AIHW 2024).
After adjusting for different population age structures over time, the proportion of adults aged 18 and over living with overweight or obesity increased from 57% in 1995 to 65% in 2022. Over this time, the proportion living with overweight (but not obesity) declined from 38% to 34% but the proportion of those living with obesity increased, from 19% in 1995 to 31% (Figure 1) (AIHW 2024).
See the Overweight and obesity report for more information.
Figure 1: Proportion of overweight or obesity in children and adolescents aged 5–17, and adults aged 18 and over, 1995 to 2022
Data show that in children and adolescents and adults the prevalence of overweight/obesity has generally increased from 1995 to 2022.
Notes:
1. Age standardised rates use the 2001 Australian population to account for differences in the age structure across population groups.
2. Age-standardised rates are only for adults aged 18 and over.
Source: Overweight and Obesity (AIHW 2024). For data and footnotes see data tables S4 and S11 in Overweight and obesity.
AIHW (Australian Institute of Health and Welfare) (2021) Australian Burden of Disease Study: Impact and causes of illness and death in Australia 2018 – Summary report, AIHW, Australian Government, accessed 18 October 2023.
AIHW (2023) Reducing the burden due to overweight (including obesity) and physical inactivity, AIHW, Australian Government, accessed 18 October 2023.
AIHW (2024) Overweight and obesity, AIHW, Australian Government, accessed 8 May 2024.
NHMRC (National Health and Medical Research Council) (2013) Clinical Practice Guidelines for the Management of Overweight and Obesity in Adults, Adolescents and Children in Australia, NHMRC, Melbourne, accessed 1 February 2022.
Wang Y, Chen X, Song Y, Caballero B & Cheskin LJ (2008) 'Association between obesity and kidney disease: a systematic review and meta-analysis', Kidney International, 73:19–33.