Evidence informing policy

A comprehensive, multi-sectoral approach

Weight gain is underpinned by a complex range of social, economic, educational and environmental factors.^(1-4) Evidence suggests that strategies targeting individual behaviours relating to diet, energy intake and physical activity without changing the many determinants of these behaviours are unlikely to achieve significant or sustained outcomes. ^(1-4)

Central to this approach is the need to change a range of environmental elements to support people to eat well and be active. This approach requires action from all levels of society, including individuals and families, industry, schools, workplaces, communities, and health and other professionals, with a steering role for governments.⁽¹⁾ A comprehensive, multi-sectoral approach to improving physical activity levels and nutrition aimed at reducing overweight and obesity at the population level in Australia is needed. The National Obesity Strategy is intended to serve as a framework for this.

In Australia, some population groups, including Australians in lower socioeconomic groups⁽⁵⁾, people living in rural and remote areas⁽⁶⁾ and Indigenous Australians⁽⁷⁾, have higher rates of obesity and overweight, poor nutrition and physical inactivity. Issues such as access to affordable healthy foods and opportunities to engage in physical activity are likely to be major contributing factors.⁽¹⁾ Therefore, an important part of a comprehensive, multi-sectoral approach to obesity prevention in Australia will be the development and implementation of specific, culturally sensitive interventions addressing the needs of these high risk groups.⁽¹⁾

This chapter focuses on the evidence informing our policy positions, including the evidence for interventions for the prevention of overweight and obesity, improving diet and physical activity.

Environments that help the community eat well

Front of pack labelling

Front of pack labelling has been shown to be effective in assisting consumers to identify healthier food options at the point of sale,^(8-11) and help guide their selection processes and in doing so may improve health outcomes. However, nutrition and health claims on food labels or in advertising can position unhealthy foods as delivering nutritional or health benefits and undermine purchase decisions. A number of front of pack labelling formats are in use globally, with different levels of effectiveness. Systems with an interpretive element to indicate the healthiness of a product generally perform better in assisting consumers to identify healthier foods.^(12-15) A recent review conducted by IARC established that the Nutri-score was more effective at helping consumers identify a healthier option when compared to other nutrition labels.⁽¹⁶⁾

Labelling systems include:

Summary indicators:

These labels provide a food with an overall assessment of nutritional quality (for example- Health Star Rating, Nutri-score, an overall tick of approval).

Nutri-score⁽¹⁶⁾: ranks the nutritional quality of food and beverages using five difference colours to classify food products into five categories from category A (dark green), indicating higher nutritional quality, to category E (dark orange), indicating lower nutritional quality.

Health Star Rating: provides a rating from ½ star (unhealthy) to 5 stars (healthy).

Nutrient specific systems:

a) Interpretive systems: provide guidance on a set of nutrients. For example, Chile’s system of black warning labels shaped like stop signs for food and drinks that exceed limits for sugar, salt, saturated fat and calorie.

b) Reductive systems: provide information on a specific nutrient only.

Nutrient warning labels:

These labels are applied to food and beverages where the product exceeds a specific threshold for various risk nutrients.

NOVA⁽¹⁷⁾: classifies food according to the level of processing it has undergone. The classification system has four food categories: (1) unprocessed or minimally processed foods, (2) processed culinary ingredients, (3) processed foods, and (4) ultra-processed foods.

There is evidence that front of pack food labelling provides an incentive for food manufacturers to increase the availability of healthier products through product reformulation, including reducing sugar, fat and/or salt and increasing fibre intake in their products. For example, the adoption of the Choices logo in the Netherlands⁽¹⁸⁾, mandatory trans-fat labelling in South Korea, Canada, and the US^(19-21), and the Pick the Tick logo in New Zealand⁽²²⁾, led to reformulations that improved the nutrient profile of products in these markets. Current evidence ^{(23, 24)} has confirmed that the implementation of the Health Star Rating system is driving food manufactures to make positive changes to their products to ensure a more favorable Health Star Rating.

Nutrition content claims on food labels

Food companies use nutrition content claims to highlight positive aspects of products that may have negative attributes, such as marketing a high-sugar product as low-fat.⁽²⁵⁾ This is a problem as consumers perceive foods carrying claims as healthier than foods without claims, regardless of their nutrition composition ^{(26, 27)}, and claims influence purchases.⁽²⁸⁾ Research in Australia has found that up to 79% of products carrying nutrition content claims in some food categories are not healthy enough to make a health claim.⁽²⁹⁾

Food marketing to children

Children in Australia are exposed to a high number of advertisements for unhealthy food on television and through non-broadcast media. Between 54% and 82% of food advertising during television programs popular with children is for unhealthy foods and beverages that are high in fat, salt and sugar.^(30-32) Substantial exposure also occurs through the internet ^{(33, 34)} and packaging promotions.^(35-37)

These exposures to unhealthy food result in increased consumption of energy dense food in children.^{(38, 39)} Reducing children’s exposure to unhealthy food marketing has been identified as one of the most cost-effective strategies to prevent obesity, in part because it has the potential to reach a large population of children, and therefore, is a key area for action.^(40-42) Evidence indicates that food marketing to children generates positive beliefs about the advertised products, and influences food preferences, purchasing requests and consumption, as well as dietary habits and health status.^(43-47) Evidence shows that children do not understand the persuasive intent of food marketing; that food marketing influences children’s food preferences and generates positive beliefs about the foods advertised.⁽⁴⁵⁾ Further, the high level of unhealthy food advertising may limit the effectiveness of social marketing campaigns promoting healthy foods and lifestyles.⁽⁴⁸⁾

Current food marketing regulations are limited, and only apply to specific children’s programming on television.⁽⁴⁹⁾ The highest numbers of children watch prime time commercial television between 5:30pm and 9:30pm when the regulations do not apply.⁽⁵⁰⁾ Advertising industry codes are in place, but their effectiveness is limited as they are typically voluntary, permissive, and poorly monitored and enforced.^{(32, 51-54)}

Community support for food marketing regulation

The Australian community supports government regulation of food and beverage advertising (55, 56). Studies have shown strong support for restricting unhealthy food advertising to children on television (79% support) and on digital media (76% support).^{(56, 57)}

Food reformulation

Many processed foods are high in salt, sugar, fat and energy making them low in overall nutritional quality. Improving the nutritional quality of the food supply through product reformulation and innovation has enormous potential for improving population nutrition and health.⁽³⁾ Reducing portion sizes of processed foods, which have increased substantially in recent years, also has the potential to decrease energy intake as evidence indicates that people tend to consume more kilojoules when they are presented with larger portions of food and beverages.⁽³⁾

Internationally, there has been some success with food reformulation having a positive health impact such as reducing intake of salt. A systematic review showed that salt could be reduced by 40% in breads and 70% in processed meats, without impacting consumer acceptability, suggesting there are opportunities for food manufacturers to make their products healthier.⁽⁵⁸⁾ In the UK, an analysis of salt reduction initiatives has shown that population salt intake has been reduced by 15% over 7 years, potentially avoiding 6,000 cardiovascular disease deaths and saving the economy £1.5 billion each year.⁽⁵⁹⁾

In Australia, food reformulation could be a cost-effective preventive health measure. An evaluation of 123 Australian preventive health interventions found that limiting the salt content of three basic foods (bread, cereals and margarine) on a mandatory basis, would have a large impact on population health. This intervention was shown to not only be cost-effective, but cost saving.⁽⁶⁰⁾

Economic interventions

Economic interventions, such as taxation, grants and subsidies can provide incentives and disincentives to help modify health behaviours relating to poor diet and physical activity.⁽¹⁾

There are increasing calls for the Australian Government to follow the lead of other countries, including the UK, Mexico, and France, and develop a policy for taxing and subsidising food and drink to promote dietary change and reduce the burden of chronic disease.

A systematic review has shown that taxes and subsidies are likely to be effective in improving consumption patterns contributing to obesity.(61) Soft drink taxes and healthy food subsidies have been shown to be effective in promoting changes in dietary habits.⁽⁶²⁾

An Australian study examined the cost-effectiveness of combining taxes on unhealthy foods and subsidies on healthy foods.⁽⁶³⁾ The combination of the taxes and subsidies could avoid the loss of as many as 470,000 disability-adjusted life years in the Australian population, at a net cost-saving of AU$3.4 billion to the health sector. The largest gains in health were achieved by a sugar tax. A fruit and vegetable subsidy is cost-effective when added to a package of taxes.^{(63, 64)}

In Australia, there are a lack of financial incentives and disincentives to support increased physical activity. The fringe benefits tax for private motor vehicle use promotes the use of private cars rather than active transport (such as walking, cycling and public transport), encouraging inactivity.⁽¹⁾ The NSW government has introduced the Active Kids program that encourages kids to be more active by subsidising participation fees of recreational activities.⁽⁶⁵⁾

Public education

Public education campaigns utilise commercial marketing principles and mass media to distribute and promote public health messages. Increasingly, social marketing has been used as a public education strategy. The value of social marketing as a public education tool – as seen in tobacco control – is its role in influencing attitudes and shifting cultural norms regarding health behaviours.

Evidence increasingly shows that well designed and executed social marketing campaigns on health issues that are sustained over time can be effective in changing health knowledge, beliefs, attitudes and behaviours across large populations.^{(48, 66, 67)} While the bulk of current evidence relates to tobacco control, social marketing interventions have also been shown to be effective in increasing physical activity and improving nutrition.^{(48, 68-71)}

More recently, studies have highlighted the characteristics of effective obesity prevention mass media campaigns^{(72, 73)}, showing that presenting hard-hitting information about the health consequences of overweight and obesity appear most effective. These findings are consistent with the literature on anti-smoking mass media campaigns.^{(72, 73)}

In a public health setting, public education mass media campaigns are often supported by complementary messaging through other channels including healthcare providers and community programs.⁽⁷⁴⁾ This allows for integrated universal and targeted approaches, so that social marketing campaigns are supported by local level initiatives tailored to the needs of specific communities. The LiveLighter® public education campaign to address overweight and obesity includes mass media, advocacy initiatives and education and support tools. The first campaign phase highlighted that overweight and obesity was a risk factor for chronic disease. Evaluation showed it successfully raised awareness of the issue as well as increasing intention to change behaviour.⁽⁷³⁾ The second phase of the campaign highlighted the link between sugary drink consumption and weight gain. Evaluation showed that overweight respondents reduced their intake of sugar sweetened beverages.^{(75, 76)}

The effectiveness of social marketing interventions is improved when they are one component of a comprehensive approach targeting population health behaviours; outcomes of these interventions are generally better when they are supported by complementary policies and programs to support behavioural change, and competing marketing messages are restricted.⁽⁷⁷⁾

The physical environment

A range of components of the physical environment have been shown to have a significant impact on the physical activity levels and obesity rates of individuals and communities.^{(1, 2, 78)}

Evidence suggests that 'walkable' environments are associated with decreased rates of obesity and higher levels of physical activity.^(79-81) Key characteristics of a walkable environment include mixed land use, higher residential density, street connectivity and design, availability of footpaths, attractive surrounds and perceptions that the environment is safe.^{(1, 3, 82, 83)} Positive associations have been shown between walkability, street connectivity and residential density/urbanisation, and total walking for transport in adults aged 65 years and older.⁽⁸⁴⁾

Physical environments designed to facilitate active transport such as cycling, walking and public transport are associated with increased physical activity.^{(81, 83)} Infrastructure enabling active transport between residential, commercial and business areas, and access to recreational facilities and sporting infrastructure are key components of such environments.^{(81, 83)}

There is some evidence that the physical environment can influence diet - improved access to healthy foods may increase consumption of healthy food.⁽⁸³⁾ There is evidence from the US to suggest that neighbourhoods with better access to supermarkets and fewer fast food outlets tend to have healthier diets and lower levels of obesity.^{(3, 85, 86)} A Canadian study has shown that having grocery stores within close proximity to place of residence is associated with a lower likelihood of regular sugar-sweetened beverage consumption (a probable risk factor for weight gain and obesity), among pre-school children.⁽⁸⁷⁾