Obesity is a major public health issue in Australia. A previous analysis, which included people born up until 1976–1980, indicated that the prevalence of obesity at any given age had increased with each more recently born cohort. This analysis aimed to use more recent data to compare obesity prevalence at any given age between different birth cohorts.
Using data from the 1995 National Nutrition Survey, 2007–08 National Health Survey, 2011–12 Australian Health Survey and 2014–15 National Health Survey, birth cohorts were constructed based on approximated year of birth of survey participants. Obesity prevalence (as classified by a BMI based on measured height and weight of equal to or more than 30) among each birth cohort at each survey was then calculated.
Obesity prevalence during early adulthood for those born in the mid-1990s was approximately double that for those born in the mid-1970s. Similar differences in obesity prevalence were seen at other given ages.
The findings of this analysis indicate that obesity prevalence was substantially higher among more recently born birth cohorts, and these increasing trends are continuing at several given ages, including younger ages. Given obesity is a risk factor for several chronic diseases, the observed earlier onset of obesity could be followed by earlier onset of chronic disease among more recently born birth cohorts.