In Wales, where 62% of the population is either overweight or obese, improving food environments and enabling people to live healthier lives, is a critical social challenge. Data on the prevalence of obesity and its drivers is key to the design, trialling and scaling of effective solutions. In an ideal world, an entire data ecosystem - containing accurate, timely and granular data on the prevalence of obesity, people’s diets and the food environment - would support policy makers in their efforts. But what happens when much of that data isn’t collected?

We’ve isolated the missing publicly available data or ‘data gaps’ in this ecosystem which, if filled, could support Welsh Government, Nesta and other stakeholders to reduce the prevalence of obesity in Wales. Through a combination of desk research and conversations with experts, we identified 27 gaps in areas ranging from the available data on the nutritional content of food and drink to data on exposure to food advertising and promotions. Each gap was assigned a priority level to convey the importance of closing the gap given current policy priorities, the effort required to close the gap and potential impact of providing this data.

Seven high-priority data gaps were identified, reflecting their magnitude, impact and urgency. Strikingly, four of these seven data gaps hinder efforts to address childhood obesity. For several of these gaps, comparable data is already available for England and Scotland.

• Childhood obesity: Regular and systematic monitoring of body weight in children from: (i) early years to (ii) primary school age and (iii) adolescence is severely lacking, along with limited data on their (iv) daily diets and energy intake. Filling these gaps, in a sensitive and cautious manner, would allow more timely identification of at-risk children and the design of more effective interventions to reduce prevalence of childhood and long-term childhood-onset obesity.
• Adult diets: Limited data on what we eat represented a significant data gap as did the lack of data on the impact of food consumed outside the home on diets and obesity. Improving data on adult diets would allow more accurate targeting of harmful foods for reformulation, and measures such as restrictions on price and placement promotions; which show potential to be impactful.
• Local affordability: While the Healthy Weight Healthy Wales strategy highlights the importance of improving diets, a lack of localised data prevents tracking the affordability of healthier food for different groups across Wales. The recent rise in food and energy costs has only increased the need for more interventions around affordability. Data on the affordability of healthier food could support the implementation of subsidies, healthy food voucher schemes, or promoting available options that are cheaper and healthier.
• Publicly procured food: The Healthy Weight Healthy Wales strategy calls on Welsh food companies to reduce the energy content of the food and drink they produce. Foods served in locations where the government has greatest control over the food on offer (e.g,. schools, hospitals and other public sector workplaces), would be a sensible starting point. However, we found limited data on publicly procured foods, which would be of great value to target and track such efforts.

The good news is that it is relatively straightforward to begin addressing many of these data gaps. Suggestions for how some of these gaps could be filled include: funding a boosted sample for the National Diet and Nutrition Survey to address critical data gaps on diets in both adults and children, and cautiously extending the Child Measurement Programme to include older primary school children and adolescents.

More challenging will be the creation of new infrastructures and networks for gathering data on the likes of online exposure to food advertising for example. Nevertheless, our findings provide a starting point for strategic and coordinated action to enhance the data available to support obesity reduction in Wales, and Nesta would be keen to explore how we could work with other organisations to start doing just this.