Overweight and obesity
For all age groups except 5–14, 55–64 and 65–74, those born most recently were significantly more likely to be overweight or obese than those born 10 years earlier. The largest absolute difference was at age 75–84, where an additional 7 in every 100 adults were overweight or obese at age 75–84 in 2017–18 compared with 2007–08.
The 5–14, 55–64 and 65–74 age groups followed a similar pattern, however the difference in the prevalence of overweight and obesity between the birth cohorts was not statistically significant (Figure 1, tables S2 and S3).
Obesity
For all age groups except 5–14 and 15–24, those born most recently were significantly more likely to be obese than those born 10 years earlier. The largest absolute difference was at age 75–84, where an additional 11 in every 100 adults were obese at age 75–84 in 2017–18 compared with 2007–08.
The 5–14 and 15–24 age groups followed a similar pattern, however the difference in the prevalence of obesity between the birth cohorts was not statistically significant (Figure 1, tables S2 and S3).
Severe obesity
In this report, severe obesity is defined as a BMI of 35 kg/m2 or more in adults. The analysis of severe obesity is limited to adults due to a lack of consensus on the definition for children and adolescents.
For all adult age groups except 35–44, those born most recently were significantly more likely to be severely obese than those born 10 years earlier. The largest absolute difference was at age 65–74, where an additional 7 in every 100 adults were severely obese at age 65–74 in 2017–18 compared with 2007–08.
The 35–44 age group followed a similar pattern, however the difference in the prevalence of severe obesity between the birth cohorts was not statistically significant (Figure 1, tables S2 and S3).
Abdominal obesity
In this report, abdominal obesity is defined as a waist circumference of 102 cm or more in men and 88 cm or more in women (WHO 2000). The analysis of abdominal obesity is limited to adults due to a lack of consensus on the definition for children and adolescents.
For the 45–54, 65–74 and 75–84 age groups, those born most recently were significantly more likely to be abdominally obese than those born 10 years earlier. The largest absolute difference was at age 45–54, where an additional 9 in every 100 adults were abdominally obese at age 45–54 in 2017–18 compared with 2007–08.
The 25–34 and 35–44 age groups followed a similar pattern, however the difference in the prevalence of abdominal obesity between the birth cohorts was not statistically significant, and the 55–64 age group showed little difference between the birth cohorts (Figure 1, tables S2 and S3).
Median BMI
Analysis of the median BMI (or 50th percentile) shows the differences between cohorts in what is considered a typical BMI. This analysis is limited to adults due to the age- and sex-specific BMI cut-offs for measuring overweight and obesity in children and adolescents.
For all adult age groups, the median BMI of those born most recently was significantly higher than that of those born 10 years earlier (Figure 1, Table S4). The largest absolute difference was at age 75–84, where the median BMI was 1.4 kg/m2 higher at age 75–84 in 2017–18 compared with 2007–08.
References
ABS (Australian Bureau of Statistics) 2009. Microdata: National Health Survey, Basic and Expanded CURF, 2007–08. ABS cat. no. 4324.0.55.001. Findings based on Expanded Confidentialised Unit Record File analysis. Canberra: ABS.
ABS 2019. Microdata: National Health Survey, 2017–18. ABS cat. no. 4324.0.55.001. Findings based on Detailed Microdata analysis. Canberra: ABS.
WHO (World Health Organization) 2000. Obesity: preventing and managing the global epidemic. Report of a WHO consultation. WHO Technical Report Series 894:i–xii, 1–253.