The impacts of a 20% sugar-sweetened beverage taxation on body mass index, implementation costs, revenue, and employment in Thailand

Abstract

Introduction: Obesity is a growing public health problem in Thailand. The World Health Organisation (WHO) recommends sugar-sweetened beverage (SSB) taxes to address obesity. Many countries have assessed the impacts of SSB taxes on consumption behaviours and health outcomes, however, there is no such evidence for Thailand. The objectives were to estimate the impacts of a 20% SSB tax on body mass index (BMI), implementation costs, revenue, and employment, in order to provide evidence for policy makers in Thailand. Methods: A base evidence model was built to calculate the point estimate impacts of a 20% SSB tax on SSB consumption, energy intake, BMI, and overweight/obesity prevalence. Literature-based estimates were included for pass-on rate, price elasticity, energy compensation, and energy balance to weight change. Implementation costs were calculated using the WHO-CHOICE framework and the wage rates of tax administrators. The revenue gain was estimated from the post-tax SSB consumption and a tax rate. The impact on employment was based on a U.S. modelling study applied to the Thai context. Results: A 20% SSB tax is estimated to reduce overall SSB consumption by 26% and BMI by 0.26 kg/m2 for men, 0.20 kg/m2 for women, and 0.20 kg/m2 for boys and girls. Overweight or obesity prevalence would decrease by 2.76% for men and 1.70% for women. Validity estimates using alternative model pathways gave similar results. The tax implementation would cost around 385 million Baht for the first year, and about 416 million Baht for 10 years. The annual revenue gain would be approximately 13 billion Baht. The tax intervention would also affect employment by increasing around 14,600 jobs. Conclusions: This base evidence model provides the basic structure and point estimate parameters for a full cost-effectiveness analysis on the impacts of a SSB tax. The findings from this study are similar to other published models, although many model parameters need strengthening with uncertainty estimates. The key findings from this study have added the evidence on the effectiveness of the SSB tax in Thailand. This should inform policy makers in considering the SSB tax as an effective intervention to tackle the increasing obesity prevalence.