Sixty-three percent of Australians are overweight, up from 49 percent in 1980, a study published Thursday showed, highlighting the country's growing obesity problem.
Australasia—Australia, New Zealand, New Guinea and neighboring islands in the Pacific Ocean—saw the largest absolute increase in adult obesity worldwide over the past 34 years, rising to 29 percent from 16 percent in 1980. It also saw the largest jump in adult female obesity to 30 percent from 17 percent.
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People are considered obese when their body mass index—a measurement derived by dividing a person's weight by the square of their height—exceeds 30.
The study, which was conducted by the University of Washington's Institute of Health Metrics and Evaluation (IHME) and published in "The Lancet" medicine journal, found over 68 percent of Australian men and 56 percent of women are overweight or obese, the second largest gender gap in overweight/obesity globally.
The study also found that Australian children are at risk; around 24 percent are either obese or overweight, up from 16 percent in 1980.
Tipping the scale
While obesity has increased globally over the last 30 years, the study found variations across countries.
In developed countries, increases in obesity that began in the 1980s and accelerated from 1992 to 2002 have slowed since 2006. Conversely, in developing countries, where almost two-thirds of the world's obese people currently live, increases are likely to continue.
Health experts are particularly worried about the risks associated with obesity: "In the last three decades, not one country has achieved success in reducing obesity rates, and we expect obesity to rise steadily as incomes rise in low- and middle-income countries in particular, unless urgent steps are taken to address this public health crisis," said Professor Rob Moodie from the School of Population and Global Health at the University of Melbourne.
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According to Alan Lopez, laureate professor at the University of Melbourne, action is required: "Health authorities across the region need to take the population health consequences of weight gain much more seriously"
"Unlike tobacco control, there is very little evidence that public heath campaigns or industry regulatory mechanisms are yet having an impact," he added.
The study is entitled the "Global, regional, and national prevalence of overweight and obesity in children and adults during 1980-2013: a systematic analysis for the Global Burden of Disease Study 2013."