Food taxes: what type of evidence is available to inform policy development?

Summary  Once dispatched to the bottom draw of policy options to address unhealthy eating, food taxes now seem back in the out tray of European policy makers. Even David Cameron made an offhand quip recently suggesting that this is something the British Government might explore. While the purpose of developing food taxes is likely their potential to raise money for national treasuries, governments have justified them on health grounds. But, what evidence is available that can inform policy development in this area from a health perspective? Most obvious are the studies that model different scenarios for taxes. Yet these studies form a relatively small part of the potential evidence‐base. The largest proportion of existing research on food prices has simply measured food prices in the marketplace and drawn hypotheses about the dietary implications. Other studies have estimated the costs of actually consumed diets. Another set of studies have quantified an association between price of specific foods and diet from real world data. Others have likewise taken a quantitative approach, but in experimental settings. A particularly large group of studies are qualitative – those asking consumers if and/or how their food choices are influenced by prices. The final type of study combines qualitative and quantitative methods. This paper examines the relevance of these different types of evidence as information for policy development in this area.