Research Roundup
Estimated changes in free sugar consumption one year after the UK soft drinks industry levy came into force: controlled interrupted time series analysis of the National Diet and Nutrition Survey (2011–2019)
2 August 2024
There is evidence linking the high consumption of sugar-sweetened beverages (SSBs) to a high risk of poor health outcomes, such that the WHO recommends taxation of SSBs to reduce the overconsumption of free sugars and improve health.
As background, the UK soft drinks industry levy (SDIL) was announced in March 2016 and implemented in April 2018, encouraging manufacturers to reduce the sugar content of soft drinks. Previous studies had shown that a year after the UK SDIL was implemented, there was evidence of a reduction in the sugar content of soft drinks and households. On average, the reduced amount of sugar purchased from soft drinks was 8 g/week with no evidence of substitution with confectionary or alcohol. However, a lack of available data meant it was challenging to examine substitution for purchasing other sugar-containing foods and drinks.
A recent study (1) investigated the changes (absolute and relative) in individual-level consumption of free sugars (these are sugars added to a food or drink plus the sugar component of honey, fruit juice and fruit juice concentrates) in the whole diet and from soft drinks alone 11 months after SDIL implementation. These changes were compared with a counterfactual scenario of no SDIL. This allowed the authors to consider possible substitutions with other sugar-containing food items. The data were collected from 7999 adults and 7656 children across an 11-year span.
Trends in free sugar consumption before the announcement of SDIL in April 2016 were used to estimate counterfactual scenarios of what would have happened if the SDIL had not been announced or come into force.
Results indicated that before the SDIL announcement, there were absolute reductions in the daily consumption of free sugars from the whole diet in children and adults. Following the SDIL announcement, free sugar consumption from soft drinks and the whole of diet appeared to decline even more than expected if the SDIL had not been announced and implemented.
In children this was equivalent to a reduction of 4.8 g of free sugars/day from food and soft drinks, of which 3 g/day came from soft drinks alone, suggesting that the sugar reduction in the diet was due mainly to a reduction of sugar from soft drinks. In adults, however, sugar reduction appeared to come equally from food and drink with an 11 g reduction in food and drinks combined, of which 5.2 g was from soft drinks only.
While there were absolute reductions in free sugars, no significant reduction in the percentage of energy from free sugar occurred. This applied to both soft drinks and total diet for children and adults. The authors surmised this is because the energy intake from free sugar was reducing simultaneously with overall total energy intake.
Key strengths of this study were the use of nationally representative data on individual consumption of food and drink in and out of the home, a consistent 4-day food diary assessment, and 11 years of continual data collection. The limitations were the inability to examine impacts across sociodemographic groups and consideration of other interventions that might have led to a reduction in sugar across the population. For example, the authors noted the UK government’s voluntary sugar reduction programme implemented across overlapping timelines (2015–2020).
Reference
- Rogers NT, Cummins S, Jones CP, et al. J Epidemiol Community Health 2024;0:1–7. doi:10.1136/jech-2023-221051 https://doi.org/10.1136/jech-2023-221051
