How do sugar-sweetened beverage taxes really work? A complexity-informed synthesis to guide best-practice development

Long term diseases drive poverty, increase healthcare costs and lead to a huge number of early deaths worldwide. Taxing unhealthy products may help prevent such diseases. Taxes on sugary drinks have been introduced in 35+ countries. However, we do not fully understand how these taxes work, or what is the best type of sugary drink tax to maximize health impact. Although these takes are intended to increase prices, they may also work in other ways. I will use existing methods to assess how these taxes work, choosing the most suitable research methods at each stage of my research. I will also evaluate how different tax designs compare, and explore whether these taxes work differently in different richer and poorer countries. My findings should help us to develop better sugary drink taxes that are more likely to improve health. This will contribute importantly to preventing long term conditions worldwide.