Nesta and BIT conducted an online experiment to better understand the public’s attitude towards different interventions aimed at reducing obesity. We also explored whether attitudes were affected by framing messages differently, and who the messengers were.

From campaigns encouraging families to swap their chocolate breakfast cereal for a healthy bowl of porridge to sugar-taxes aimed at persuading food companies to reformulate their high-sugar products, the government, food industry and the third sector have a wide range of policies in their toolbox when it comes to reducing obesity. However, some policies aimed at reducing obesity can run into public opposition, making their implementation less likely. Further, there are examples in the past of campaigns that have been criticised for reinforcing stigma and fat-shaming; as such, these may actually have contributed to weight gain and poor health.

Several factors may win public support for obesity interventions. For one, beliefs about the causes of obesity may shape perceptions on how best to tackle it; the way we talk about the drivers of obesity could influence public support for policies that seek to reduce it. Support is also likely to be influenced by public views on how and when government should intervene in daily life, so using messengers from outside government could be influential in increasing support for specific government interventions..

Whatever the mediating factors, what people think matters: if governments are unwilling to introduce unpopular interventions, then progress on tackling obesity is at risk.

Key findings:

• Interventions which participants found to be the most acceptable are also the ones they perceived to be most effective. However, the interventions that were reported to be least effective and least acceptable are those that are likely to have the greatest potential for promoting healthy eating at the population level. Addressing the disconnect between the evidence base and public understanding may be a viable way of influencing public acceptability.
• Encouragingly, all interventions we asked about were supported by a majority of participants. However, in general interventions that involved providing information or enabling individuals to make better decisions were seen to be more acceptable than those that change, disincentivise or restrict food choices. This can be explained as stemming from the widely held, but false, belief that obesity is largely due to a lack of willpower by individuals. This adds to the growing body of evidence that changing this narrative - by looking to the media, advertising, and other societal influences that have propagated it - is an essential next step.
• Interventions receive less public support if they are communicated by the government. This suggests that using a government messenger should be avoided when proposing or communicating obesity interventions to the public. However, it raises additional questions about who or which types of organisations might be better placed to communicate this information.