What will it take to curb the rise in obesity?

Shifting a whole population towards a healthy weight requires action targeting the root causes of obesity

The headline finding from our 2003 paper was a 2.5-times increase in the prevalence of obesity since 1980, with 20.8% of Australian adults found to be obese. Reporting the national obesity prevalence for the first time since 1995, this paper was one of the key outcomes from the Australian Diabetes, Obesity and Lifestyle study (AusDiab).1 AusDiab was the first Australian national diabetes study; it showed an adult prevalence of diabetes of 7.4% and that of prediabetes (elevated blood glucose levels but below the cut-point for diabetes) at 16.4%.2 These figures meant that prevention of the twin epidemics of obesity and diabetes was placed very much on the national agenda. AusDiab went on to become a longitudinal study, with the follow-ups of the cohort at 5 and 12 years providing invaluable data for studying obesity, diabetes, prediabetes, hypertension and kidney disease in individuals as they age. The more than 200 papers now published using data from this study have played an important role in influencing national public health policy and action.

With the prevalence of obesity continuing to climb since the baseline AusDiab survey (28.3% in the 2011–12 National Health Survey3), it is becoming clear that the lifestyle change programs and medical interventions that are often successful in trials and for individuals are effectively individual sandbags against the flood of obesity. Successfully shifting a whole population towards a healthy weight is likely to also require action targeting some of the root causes of obesity. Our increasingly sedentary and inactive lifestyles in combination with an environment full of cheap, tasty, heavily marketed and energy-dense foods make us highly susceptible to weight gain. Although we are each responsible for our own behaviour, these environmental and cultural factors combine to effectively conspire against healthy choices.4 In addition, a focus on adult lifestyles, although important, ignores the increasing body of data suggesting that the genesis of adult obesity is biological and cultural factors operating very early in life.5

A promising next generation of environmental obesity prevention initiatives include the excellent work done to improve the school food environment in many countries (now championed in the United States by First Lady Michelle Obama6), whole-of-community interventions such as the Healthy Together Communities program in Victoria7 and excellent work by researchers,8 retailers9 and others10 to change the way food is marketed and sold. Obesity prevention in mothers and in infants11 and prevention of excess gestational weight gain are further promising approaches. The combination of initiatives such as these will hopefully mean that when the Journal celebrates another decade, we will also be finally able to celebrate a reduction in Australia's obesity prevalence.