Citation
Stacey, Nicholas; Edoka, Ijeoma; Hofman, Karen; Swart, Elizabeth C.; Popkin, Barry M.; & Ng, Shu Wen (2021). Changes in Beverage Purchases following the Announcement and Implementation of South Africa’s Health Promotion Levy: An Observational Study. Lancet Planetary Health, 5(4), e200-8. PMCID: PMC8071067Abstract
Background: In 2016, South Africa announced an intention to levy a tax on sugar-sweetened beverages (SSBs). In 2018, the country implemented an SSB tax of approximately 10%, known as the Health Promotion Levy (HPL). We aimed to assess changes in the purchases of beverages before and after the HPL announcement and implementation.Methods: We used Kantar Europanel data on monthly household purchases between January, 2014, and March, 2019, among a sample of South African households (n=113 653 household-month observations) from all nine provinces to obtain per-capita sugar, calories, and volume from taxable and non-taxable beverages purchased before and after the HPL announcement and implementation. We describe survey-weighted means for each period, and regression-controlled predictions of outcomes and counterfactuals based on pre-HPL announcement trends, with bootstrapped 95% CIs, and stratify results by socioeconomic status.
Findings: Mean sugar from taxable beverage purchases fell from 16·25 g/capita per day (95% CI 15·80-16·70) to 14·26 (13·85-14·67) from the pre-HPL announcement to post-announcement period, and then to 10·63 g/capita per day (10·22-11·04) in the year after implementation. Mean volumes of taxable beverage purchases fell from 518·99 mL/capita per day (506·90-531·08) to 492·16 (481·28-503·04) from pre-announcement to post announcement, and then to 443·39 mL/capita per day (430·10-456·56) after implementation. Across these time periods, there was a small increase in the purchases of non-taxable beverages, from 283·45 mL/capita per day (273·34-293·56) pre-announcement to 312·94 (296·29-329·29) post implementation. When compared with pre-announcement counterfactual trends, reductions in taxable beverage purchase outcomes were significantly larger than the unadjusted survey-weighted observed reductions. Households with lower socioeconomic status purchased larger amounts of taxable beverages in the pre-announcement period than did households with higher socioeconomic status, but demonstrated bigger reductions after the tax was implemented.
Interpretation: The announcement and introduction of South Africa's HPL were followed by reductions in the sugar, calories, and volume of beverage purchases.
URL
http://dx.doi.org/10.1016/S2542-5196(20)30304-1Reference Type
Journal ArticleYear Published
2021Journal Title
Lancet Planetary HealthAuthor(s)
Stacey, NicholasEdoka, Ijeoma
Hofman, Karen
Swart, Elizabeth C.
Popkin, Barry M.
Ng, Shu Wen
Article Type
RegularPMCID
PMC8071067Data Set/Study
Kantar EuropanelContinent/Country
South AfricaORCiD
Popkin - 0000-0001-9495-9324Ng - 0000-0003-0582-110X