Sixty per cent of adult Australians are either overweight or obese, and thus at increased risk of serious diseases such as type 2 diabetes, heart disease and cancer. On both individual and societal levels, excess body weight has far-reaching ramifications on quality of life, life expectancy and healthcare costs, making it a modern public health challenge.
Obesity is caused by a complex combination of lifestyle, environmental and biological factors. Changes in the global food system, which is producing more processed, calorie-dense foods, increasingly time-poor lifestyles and the advent of the computer age has led to an imbalance between food consumption and energy expenditure through physical exercise.
Beyond these modifiable factors are others that we can’t control, with our biology and genetic make-up contributing at least 40% to our bodyweight and shape. Our biology also includes hormonal, metabolic and nervous system factors that may play an important role not only in the development of obesity but also in the pursuit to lose weight.
Weight reduction through calorie restriction is not always successful, and there is considerable variation in the weight loss achieved by different people. Beyond behavioural factors such as dietary compliance and exercise level, and treatment factors such as diet composition, length of treatment and absence or...