DRAFT Australian Dietary Guidelines - Eat For Health

4.1.3 Causes of overweight and obesity in the population
Healthy body weight results from an appropriate balance between energy intake and expenditure
(of which physical activity is a component) [89, 688, 723]. At the population level, there is
increasing evidence that excess energy intake is a major contributor to current energy imbalances
[88, 723-728].
4.1.3.1 The obesogenic environment
Obesity is a complex condition mediated by an individual’s metabolism and behaviour as well as
societal and environmental factors.
Although some genetic factors may increase an individual’s susceptibility to being overweight or
obese, the dramatic increases in prevalence of overweight and obesity over the past three to four
decades without any major change in the gene pool suggests that socio-environmental factors are
primarily responsible for the current epidemic [88, 89, 685, 688, 726, 727, 729]. Significant socioenvironmental
changes during this period include, but are not limited to:
changes in the food supply, particularly increased availability and decreased relative cost of
foods which tend to be higher in energy density and relatively nutrient-poor [730]
increased availability and marketing of energy-dense, nutrient-poor foods and drinks
urban design which reduces energy expenditure during daily activities and increased
reliance on car and labour-saving devices [726, 731]
reduced perceptions of safety leading to fewer opportunities for physical activity [732, 733]
economic and consumer changes, such as a greater number of females in the paid
workforce, decreased food literacy and cooking skills, and greater reliance on convenience
and takeaway foods [728, 729, 734].
These changes all promote excess weight gain by fostering consumption of energy-dense and
relatively nutrient-poor foods and/or reduced physical activity [726, 735-738].
Against such social and physical environments, overweight and obese individuals need support,
rather than criticism and discrimination. Healthy weight initiatives must achieve a balance between
individual and societal responsibility and be culturally appropriate, widely available and accessible,
particularly to disadvantaged and vulnerable groups [89, 739].
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