In this article, part of Economist Impact’s Science of Obesity series, we explore the concept of “social determinants of health” and explain the role that it plays in impacting obesity. There are widespread misconceptions that obesity is a consequence of individual choices. The reality is quite different. It is important to recognise that broader environmental factors, such as the social contexts that people are embedded in and the neighbourhoods that they reside in, play an important part in influencing obesity outcomes. 

Shockingly, obesity rates have nearly tripled since 1975.¹ The common misconception is that individuals are to blame for developing the disease through choices they make. However, in reality, obesity is driven by a complex combination of genetic and biological factors and our broader socio-economic environment, all of which are largely out of individuals’ control. The effect of genetic and biological influences on obesity is explored elsewhere in the Science of Obesity series. 

In this article, we focus on the social determinants of health—those environmental and societal conditions that affect people’s health, greatly restrict and reduce personal choice, and can increase the risk of obesity.²

Social determinants of health are the environmental conditions of where we are born, live, work, play, worship and age that have an impact on our health and quality of life.² The impact of social determinants of health can be seen globally. It has been estimated that they impact 50% of the variation in health outcomes in the US.³ For instance, there is extensive evidence that social factors, such as education, employment status and income level, can have a considerable impact on how healthy an individual is. The lower an individual’s socio-economic status, the greater their risk of obesity.⁴

The social determinants of health broadly fall into six categories that are fairly universal (Figure 1).⁵

Nobody is saying that obesity will be an easy issue to address. But Figure 3 shows that there are a large number of evidence-based interventions that address the key social determinants of health with the potential to impact on population health—both in terms of obesity and overall health status.

Focusing on a few key examples where policy interventions that address social determinants of health have positively impacted obesity and its risk factors, we see that:

• Evidence from the US suggests the provision of school meals can contribute to improvements in health and social outcomes, including obesity rates and student performance.¹⁶ Such universal policies can also play an important role in reducing stigma for children in poverty. 
• Creating healthy food environments in childcare facilities, hospitals and worksites could help to change societal attitudes and behaviours. Many countries are already mandating nutritional labels on restaurant and fast-food menus. Additional proactive steps could include providing incentives for supermarkets to be located in underserved areas.² 
• Prioritising resources to enable physical activity in areas and populations that lack access to parks or recreational spaces can also support behaviour change. Evidence shows that children with better access to public parks and recreational programmes are less likely to experience increases in body mass index (BMI) over time.¹⁷

• Many public health interventions can take years or even a generation to achieve notable results, whereas elected officials may favour tangible, shorter-term outcomes that coincide with their time in office. Sustained and constructive dialogue between health officials and political leaders is needed to address the challenges at hand and ignite strong political will for action.¹⁹

• There continues to be widespread misconceptions of obesity being a consequence of individual behaviours, despite evidence disproving this. Even among a study of over 3,000 people living with obesity, it was found that 82% believed it was completely their own responsibility.²⁰ This disconnect between public perceptions and scientific evidence needs to be rectified to generate sufficient political will—both from politicians and their electorate. 

• Food industry changes are needed when it comes to formulation, labelling, pricing and advertising.^{21, 22} However, policymakers cannot rely on industry to implement these changes. Rather, public policy interventions must mandate and incentivise such change. We can certainly learn from the experience of tobacco control to align commercial and public health interests to avoid the lobbying and bad advertising practices that sought to weaken the connection between tobacco use and lung cancer even amid the ongoing consequences of over 8m deaths per year (mostly in low- and middle-income countries).^{23, 24} 

Globally, obesity rates continue to climb thus necessitating urgent action and strong political will. A number of key approaches can be considered to reverse rising rates of obesity:

• Greater awareness and prioritisation of the various drivers influencing obesity is needed across all government departments. Health ministries, which are often tasked with the health of the nation, need to make tangible relationships with other government departments (finance, transport, trade, culture, agriculture and food industry) to explain the critical role that they can play in addressing social determinants of health. A coordinated approach involving multi-sectoral engagement and action will be necessary to halt rising rates of obesity globally.
• People power and buy-in. Changing embedded behaviours will be difficult. As such, it is necessary that local people are key actors in how their communities change the obesity landscape, from what is sold near schools, to what publicly funded physical exercise facilities are available. This will require buy-in and action from both the public and private sectors. Some countries, such as Australia, have developed comprehensive obesity action plans that include engaging people with obesity and communities at higher risk of obesity.⁷
• Prioritising a whole-of-government and whole-of-society response is needed to address rising obesity rates globally. Multilateral bodies like the World Health Organisation (WHO) have convening power, not only as technical experts but also through their ability to raise issues such as obesity globally—as the WHO did with smoking, ultimately leading to the WHO Framework Convention on Tobacco Control. The WHO is working hard to convince countries to implement a “whole-of-government, health-in-all-policies” approach.⁸ Such a multisectoral response is needed to address all domains of the social determinants of health that impact on obesity status.