South African beverage tax has reduced purchases of sugar-sweetened beverages

A new study shows that South Africa’s 2018 tax on sugary beverages led to a reduction in purchases of the beverages, which could mean purchasers are consuming less excess sugar and calories.

Shu Wen Ng, PhD, Associate Professor and Distinguished Scholar in Public Health Nutrition at the UNC Gillings School of Global Public Health, is a lead author of Changes in beverage purchases following the announcement and implementation of South Africa’s Health Promotion Levy: an observational study,” which was published April 8, 2021, in The Lancet Planetary Health. Barry Popkin, PhD, W. R. Kenan Jr. Distinguished Professor at the Gillings School, is a co-author on the paper, which was published in collaboration with partners at the University of Witwatersrand, London School of Economics, and the University of the Western Cape.

South Africa faces an increasing burden of noncommunicable diseases such as diabetes, hypertension, cardiovascular disease and cancers – diseases that research shows can be linked to increased consumption of sugar, particularly from beverages. Other countries, such as Mexico, have used policies such as taxation to successfully curb consumption of sugary beverages.

South Africa’s 2018 Health Promotion Levy, placed a tax on sugary beverages with the tax amount related to the amount of sugar. This is the first study to evaluate the impact of South Africa’s tax on sugar and caloric intake.

Researchers examined the nutritional data of over 3,000 households’ purchases before and after the tax to assess any changes in daily sugar, calories, and volume of taxed and non-taxed beverages. They found a 51% reduction in sugar, a 52% reduction in calories, and a 29% reduction in volume of beverages purchased per person per day following implementation of the tax. They also found that the relative reduction in the sugar content of taxable beverages was larger than that for volume, showing that the industry likely reformulated products.

The researchers also analyzed differences in purchasing behavior by household socioeconomic status, finding that lower socioeconomic status households had purchased more taxable beverages prior to the announcement of the tax than higher socioeconomic status households, but experienced larger reductions after the announcement and implementation of the tax.

“These results back up the impact we’ve seen from similar policies in other countries – that beverage taxes based on sugar content can help reduce excessive sugar and energy intake. Importantly, this shows that the lower income households that experience the greater burden of obesity, diabetes, hypertension, and other nutrition-related noncommunicable diseases, benefit greatly from this law,” says Ng.

“Consistent with evaluations in other countries with SSB taxes, we found that taxing sugary drinks are one an effective public health strategy to reduce the burden of health conditions linked to overconsumption of sugar” noted Popkin.

Ng and Popkin are part of the Global Food Research Program at UNC, a project of the Carolina Population Center that collaborates with partners across the globe to carefully evaluate food and nutrition policies and help to develop in-depth, longitudinal research on large-scale obesity prevention efforts.