The researchers conducted a systematic review of global data from 29 studies, with the aim of providing clarity for policymakers on the effectiveness of this widely promoted measure to deter sugar consumption and curb related NCDs like type 2 diabetes.
22 of the studies in the review employed various modelling techniques, including cost-effectiveness analyses and proportional multi-state life tables, to simulate the potential impact of SSB taxes in countries such as the US, South Africa, and the UK.
Subsequently, the review found that simulation models provided strong evidence that SSB taxation could effectively reduce the prevalence of NCDs such as type 2 diabetes, cardiovascular diseases, and obesity. The reviewed models indicated that even modest tax rates of 10% 25% could decrease NCD incidence, mortality, and healthcare costs.
Additionally, the review highlighted that the increased government revenue generated by SSB taxes could be redirected toward public health programs, enhancing overall healthcare outcomes.
Low tax rates and unchanged consumer behaviour
However, when the researchers examined empirical evidence from countries that had implemented SSB taxes, the results found a significant gap between predicted and observed outcomes of SSB taxation policies.
Seven of the studies focused on actual tax implementations, particularly in the US and UK. The findings showed that while some reduction in SSB purchases was observed, the overall effect on public health outcomes was minimal.
The review identified several reasons for the limited success of SSB taxes in reducing NCD prevalence. One major factor is that many countries set their tax rates below the World Health Organization’s (WHO) recommended minimum of 20%. As a result, the taxes on SSBs have not been high enough to meaningfully deter consumers from purchasing sugary drinks.
For instance, the UK’s SSB tax led to a 2.7% reduction in sugar purchased from taxed beverages, but this decrease was offset by a 40.2% rise in purchases of non-taxed sugary drinks.
Additionally, the study highlighted that without accompanying lifestyle changes — such as increased physical activity and better dietary choices — the SSB tax alone would be insufficient to make a substantial dent in NCD rates.
Recommendations for policy improvements
While the SSB tax has had limited success in isolation, the researchers emphasised its potential when combined with other public health initiatives. As such, the study recommended a multi-pronged approach, including public health campaigns aimed at promoting healthier lifestyles and incentives for the beverage industry to reformulate their products with less sugar.
The researchers stated that multi-actions were necessary to support the sustainability of an SSB tax, and advocated for a broader set of measures to ensure the long-term effectiveness of the tax. These actions could include stronger education efforts to raise awareness about the dangers of excessive sugar consumption and the importance of physical activity, along with industry reforms that focused on reducing sugar content in popular beverages.
Revenue generation and study limitations
While it has had limited impact on public health, the SSB tax has proven to be a valuable source of government revenue. The study’s author’s suggested that the funds generated from this tax could be used to finance healthcare improvements or public health equalisation programs, particularly in countries with under-developed healthcare infrastructure.
The researchers noted that this economic advantage was one of the policy’s most tangible benefits, even if its health effects would remain modest in the short term.
They also acknowledged several limitations the study had. Firstly, the variety of population data and differences in attributes given to each study made meta-analysis of the data impossible. However, they had also applied inclusion and exclusion criteria that allowed them to include a variety of studies, which led to a “comprehensive commentary on the state of science” and allowed them to “identify important considerations for simulation modelling, as well as future implementation of SSB policy”.
SSB tax must be part of a broader strategy
The study further stated that while SSB taxes had the potential to contribute to NCD reduction, its limited impact in this regard showed they could not be a standalone solution. Without additional policies and changes in consumer behaviour, the SSB tax’s impact would no doubt remain limited.
The researchers called for a combination of higher tax rates, public education, and industry reformulation to fully realise the potential health benefits of SSB taxation. For policymakers looking to design or refine SSB tax initiatives, this review provides crucial insights into the factors that influence the success or failure of such policies, and highlights the need for a comprehensive, multi-faceted approach to tackling NCDs.
Source: Frontiers
“Modeling and empirical evidence of the impact of implementation of sugar sweetened-beverages tax to reduce non-communicable diseases prevalence: a systematic review”
https://doi.org/10.1080/1059924X.2024.2407385
Authors: Rebecca Wheeler, et al.
