Every day we encounter dozens of messages from the media, politicians and our peers that can shape our views on policies. When we hear about a new proposal, there are lots of things we might consider – whether it sounds effective, whether it sounds fair, or whether there are downsides.

All this noise can make it difficult for people to get a clear understanding of new health policies – what they are designed to do and how they could improve their lives – however well-evidenced they are.

This means some bold but promising proposals – such as pre-watershed restrictions on junk food ads – have been delayed following industry lobbying. Ultimately, governments care what the public think, and if it is not clear that a policy has widespread support, it is more vulnerable to being delayed or abandoned.

To try and cut through this noise, Nesta and BIT conducted a randomised control trial (RCT) to measure how much being told about the rationale and/or potential benefits of a series of healthy eating policies affected the extent to which people approved or disapproved of them.

We presented a range of messages about specific health policy proposals to a representative sample of over 3,000 adults in Wales, who then rated how much they supported them.

Our research helped us to identify what really matters to people when it comes to policies that will affect their health, their families and their communities and how best to communicate a policy’s intended benefit.

We found that the way in which policies were described had a significant impact on their reception – the very same health policy can yield different levels of support depending on how it is explained and presented.

When a health policy proposal is put before the public, it is important to understand which aspects of it people really care about and that it explains how the policy relates to their concerns.

When a new policy idea gets debated, whether in the newspapers, on talk radio or around the dinner table, if the ‘pro’ argument doesn’t chime with peoples’ concerns or priorities it will struggle to garner support, even if it is well-evidenced and calculated to be cost-effective.

Based on our research, we believe there are four key principles that can help policymakers to better understand and engage with the public’s concerns, values and priorities – and so give the best possible chance for their policies to be understood and supported by the public.

There are broadly five elements that can be communicated about any policy – a description, the rationale, the effects, the objectives and the beneficiaries.

While it may seem convenient to apply a one-size-fits-all approach to messaging for policies with similar goals, Nesta and BIT’s recent research found that communicating different aspects works better for different policies.

When we emphasised that restricting temporary price reductions on unhealthy foods would aim to ‘encourage food brands to produce more healthy foods’ —–the percentage of support for the policy, minus the percentage of non-support – jumped by 14 percentage points. But for mandatory calorie labels in restaurants, this same rationale did not seem to increase public support at all. Instead, a policy description that highlighted that calorie labels empower consumers by fulfilling their ‘right to be informed about what they are purchasing’ increased net support for this policy from an already high 42% to a whopping 56%.

Other studies have suggested that effective tailored messages may include communicating evidence for the effectiveness of a policy or countering oppositions’ arguments against it.

When you need to talk about multiple policies, focus on elements that are consistently important to people across a wide range of healthy- eating policies.

Nesta and BIT’s recent study revealed that policies that were understood to be protecting consumer rights or benefitting children's health consistently garnered greater public support than other rationales. The latter is particularly well-supported by other studies, including a meta-analysis that found that interventions aimed at improving children’s health are generally more strongly supported than those targeting adults.

Of course, it may be the case that such an explanation won’t be applicable or appropriate for the policy in question, but for many health policies these two factors are often relevant.

Building public support for a policy should not be a box to check at the end, it should be considered from the get-go. Policymakers should consider what the public wants, alongside what experts say, from the beginning of the policy design process.

The best way to do this is to listen to the public, eg, through citizen advisory committees, public consultations or by running a citizens assembly. Nevertheless we can also look to what has generally been well supported in the past, such as focusing on children's rather than adults' health, using raised revenue to fund related initiatives, or using policy levers that the government already control (eg, education, public procurement, import regulation).

Implementing policies that are both impactful and popular reinforces principles of democratic representation and participatory policymaking.

To really understand what kind of messaging is going to work best for your policy and your public, where feasible, we recommend conducting your own research. Depending on what your questions are and the resource you have, research may be conducted through running a randomised control trial, focus groups, surveys, or even listening to what is being discussed on social media.

Avenues for research that could benefit a range of stakeholders with an interest in healthy eating policy include: i) understanding the techniques that industry uses to generate public opposition; ii) examining effectiveness of more informative descriptions in real-life settings, ie, beyond a laboratory experiment; and iii) deeply exploring the concerns contributing to public opposition to certain policies and support for others, such that future policy messaging and policies themselves can be better designed to cater to the public's wants and needs.

Nesta and BIT’s recent study, alongside the collective work of other researchers, has shown that we mustn’t underestimate the power of communication when developing policies that aim to make healthy eating the easy choice.

When explaining a policy to the public, it is easy for policymakers to fall into the trap of framing the conversation in a way that is shaped by institutional priorities. Our work highlights that public health bodies can benefit from communicating their policies to people in a more informed, evidence-based way. By explaining a policy in line with people's priorities and values, more people can see how it will benefit them, increasing the likelihood of them supporting it.

It is only right that policies are subject to scrutiny and criticism, but it is also right that policies are explained to citizens in a way that they can understand potential benefits clearly – and then make up their minds for themselves.