A Spatially-explicit Microsimulation Analysis of a Proposed Sugar Tax in the Australian Capital Territory

This study aimed to estimate the spatially explicit impact of a 20% proposed tax on sugar sweetened beverage (SSB) consumption across small areas within the Australian Capital Territory (ACT). The study is important in the context of informing ongoing debate around a proposal to introduce a 20% tax on the sugar content of SSBs. A microsimulation analysis was used to estimate current expenditure on SSBs and the impact of a tax at a small area level across the ACT. Population data from the Census was used to weight survey data from the Household Expenditure Survey. A microsimulation model was then applied to the data to estimate current expenditure on SSBs, and the tax impact of a 20% sugar tax on SSBs. The impact of a sugar tax falls unequally across regions of the ACT with the tax impact representing a higher proportion of income for areas with lower socioeconomic advantage. The current expenditure ($/household/annum) averaged around $300 and the tax impact of the proposed sugar tax as a percentage of income averaged around 0.12%/household/ annum. The unequal distribution of tax impact estimated by the model suggests that coupling the tax with targeted exercise and nutrition programs as well as systemic change will both be required to reduce inequalities and increase the likelihood of positive health outcomes around overweight and obesity and related conditions. at a small- area level. We also examine the differences in impact according to area- level socio- economic disadvantage.