Tackling Population Level Obesity

Poor diet and obesity combined are the leading cause of early death globally and a major cause of social inequalities in health. The obesity pandemic has been caused predominantly by changes to population level dietary patterns, resulting in widespread excess energy consumption and weight gain. The solution to the obesity pandemic will therefore involve changing dietary patterns at population level and doing so in a socially equitable way. At a policy level there is current uncertainty over which dietary patterns should be targeted to reduce population level obesity. Reducing consumption of foods high in fat, salt and/or sugar (HFSS) is a current policy priority in the UK and many countries. However, emerging findings controversially suggest that targeting foods that are characterised by being ‘ultra-processed’ (UPFs) may have a more powerful effect on reducing population level obesity. To date, no research has examined which of these overarching dietary patterns is key in explaining population level obesity. Due to a lack of basic science, there is also significant scientific uncertainty over how dietary patterns and obesity can be substantially changed at population level and achieved in a way that is socially equitable (i.e. people from all social classes benefit). Because of this, there is a need to test new population level interventions designed to reduce consumption of less healthy foods and obesity. Similarly, although reformulation of less healthy food products has been suggested to be a ‘win-win’ solution to addressing population health by reducing body weight, there is a death of biomedical research testing this proposal. The overarching aim of this multi-disciplinary programme of research is to understand how obesity can be reduced at population level. We will first examine the extent to which HFSS vs. UPF dietary patterns contribute towards weight gain and development of obesity in children and adults using epidemiology. In doing so, this research will identify which of these dietary patterns is most important in explaining population level obesity. Building on this, we will next test the impact of new population level interventions (e.g., nutrient warning labels) designed to reduce consumption of unhealthy foods using real-world consumer psychology and nutrition methods. Parallel to this work, we will conduct new experimental research which will study how human body weight is regulated in response to food energy content. In doing this, we will understand the causal impact and magnitude of change that energy reformulation of unhealthy food has on human body weight. We will then integrate data collected across the programme of research and use complex public health modelling methodology. This approach will reveal the impact that a range of new interventions (e.g., based on reducing consumption of unhealthy foods and/or on reformulation) would have on national obesity prevalence and public health, if implemented by policy makers. The research we conduct will make important academic contributions by addressing critical basis science questions relating to nutrition, body weight regulation and obesity. Our research will also have important policy implications. We will actively work alongside and disseminate findings to key stakeholders in public health advocacy, local and national government, and international public health bodies to ensure real-world impact of research. This programme of research will understand how diet drives obesity and provide the evidence required by policymakers to implement new population-level interventions to address obesity and reduce social inequalities in health.