Population health and health sector cost impacts of the UK Soft Drinks Industry Levy: a modelling study.

Abstract

Background: The United Kingdom Soft Drinks Industry Levy was introduced in April 2018, resulting both in changes in sugar levels in drinks and purchases of drinks. Both mechanisms could impact on the incidence and prevalence of raised body weight, diabetes and diet-related diseases, and therefore, have implications for economic costs to the health sector.

Objectives: To model future impacts of the Soft Drinks Industry Levy on population health and health sector costs and to estimate net monetary benefit to the health system.

Design and methods: Proportional multistate lifetable modelling study - open and closed cohort analyses.

Setting and population: All children and adults in the United Kingdom.

Intervention: The Soft Drinks Industry Levy is a two-tier levy of £0.18/l on drinks with between 5 and 8 g of total sugars/100 ml and of £0.24/l on drinks with ≥ 8 g of total sugars/100 ml.

Main outcome measures: We evaluated impact of the sugar reduction on: (1) prevalence of overweight and obesity, obesity-related diseases and dental health out to 2050 and (2) lifetime population health (measured in quality-adjusted life-years), change in costs to the health sector and the resulting net monetary benefit.

Data sources: We estimated a per person reduction in sugar from a previously published interrupted time series analysis, which found an 8.0 g/household/week (95% confidence interval 2.4 to 13.6) reduction in sugar at 1 year after implementation. Our multistate lifetable model is parameterised using data from population health monitoring surveys, the Global Burden of Disease project, the Human Mortality Database and the Office for National Statistics. Health sector costs were obtained from Department of Health and Social Care budget allocations.

Results: The model predicts that the Soft Drinks Industry Levy will reduce the prevalence of overweight and obesity in the United Kingdom by 0.18% points (95% uncertainty interval: 0.059 to 0.31) for males and by 0.20% points (0.064 to 0.34) for females. In the first 10 years of implementation, the reductions in sugar and overweight/obesity are predicted to prevent 270,000 (35,000-600,000) dental caries, 12,000 (3700-20,000) cases of type 2 diabetes, 3800 (1200-6700) cases of cardiovascular diseases and 350 (110-590) cases of obesity-related cancer. For the current United Kingdom population, it is estimated that the Soft Drinks Industry Levy will add 200,000 quality-adjusted life-years (63,500-342,000) over their lifetime and avert £174 million (£53.6-319) in their costs of health care (discounted at United Kingdom Treasury rates). At a United Kingdom Treasury value of £60,000 per quality-adjusted life-year, it is estimated that the Soft Drinks Industry Levy will produce a net monetary benefit of £12.2 billion (£3.88-20.8) for the health system.

Limitations: Modelled results assume that the effect of the Soft Drinks Industry Levy remains constant into the future. The longevity of the effect of the Soft Drinks Industry Levy has not been tested.

Conclusion: This study of the United Kingdom Soft Drinks Industry Levy tiered tax on sugar content provides further evidence that sugar-sweetened beverage taxes have the potential to achieve meaningful improvements in population health and reduce health sector spending.

Funding: This article presents independent research funded by the National Institute for Health and Care Research (NIHR) Public Health Research programme as award number 16/130/01.