Too heavy on the levy? Sugar tax is a good start but “needs to be built on,” activists argue

31 Jan 2023 --- Responding to a recent study published in PLOS Medicine arguing that the sugar tax levy has “saved 5,000 children from obesity,” campaigners are flagging potential weaknesses in the research, arguing that the levy is not solely responsible for decreasing child obesity levels. 

They further point to a lack of empirical evidence showing that obesity rates have actually declined.

“We would like to see the food and drink industry moving faster to reformulate products high in fat, salt and sugar. The latest sugar reduction report shows that overall volumes of sugar consumption in some categories are increasing, not decreasing,” a spokesperson from Sustain Children’s Food Campaign tells NutritionInsight.

Sustain further details that there is no apparent empirical decrease in obesity levels.“Introducing new legislation to restrict in-store promotions is a step forward. We’d like to see companies moving faster to remove multi-buy price offers from HFSS (high in fat, salt and sugar) products and instead put healthier products into the spotlight.”

Sustain further states that while the government has delayed the implementation of a 9 PM watershed on advertising less healthy products, it hopes that companies that want to contribute to a healthier society will start before October 2025.

“We would love to see companies doing more transparent reporting on their progress in shifting sales to healthier options and making these the affordable, appealing choice.” 

Complexity of obesity
The study was recently questioned due to limitations in the research, leading organizations to question the levy’s effectiveness because of the lack of correlation between the levy and obesity levels in year six boys and younger.

“The underlying causes of obesity are complex, so it is difficult to directly attribute a change in obesity levels to a single factor. For example, the announcement and implementation of the sugar tax occurred alongside a program of voluntary sugar reduction in other products commonly consumed by children, including biscuits, breakfast cereals, yogurts and confectionery,” says Dr. Simon Steenson, a nutrition scientist at the British Nutrition Foundation.

The spokesperson from Sustain further details that there is no apparent empirical decrease in obesity levels. “It shows that with a certain cohort of 10 to 11-year-old girls, the sugar levy might have created a dampening effect on the rising levels of obesity.”

“The soft drinks industry levy was the single biggest policy intervention during the research period, which is why the researchers think there may be an association between the change in trend and the soft drinks levy.”

Questionable estimates
Tom Sanders, professor emeritus of nutrition and dietetics at the King’s College London, UK, highlights that the soft drink levy became law in April 2018. Still, many drink manufacturers had reformulated to a lower sugar content before the deadline.

“The authors suggest there was some evidence for an association with the rate of increase in obesity to be significantly lower in year six girls but not boys associated with the period surrounding the introduction of the soft drink levy using 2013-14 as a baseline,” says Sanders.

“However, the prevalence of obesity was about 6% higher in year six boys. The claim that the soft drink levy might have prevented 5,000 children from becoming obese is speculative because it is based on an association, not actual measurements of consumption,” Sanders notes.Sanders says there are lessons to be learned from the COVID-19 pandemic, as children in low-income families were most affected by obesity.

“It is hard to discount a potential influence of changes to the availability of free sugars across these other food categories, especially among groups where these foods are more commonly consumed than sugar-sweetened beverages,” Steenson says.

Further limitations 
María Dolores del Castillo, a researcher at the Food Science Research Institute in Madrid, Spain, identifies further limitations that may implicate the findings of the study.

“Not surprisingly, differences due to age and gender are found. The authors describe the strengths and limitations of the study and compare their results with similar studies. However, the size of the populations for each sex and age group is not specified. Prevalence is mentioned and percentage data are given,” she notes.

Del Castillo adds there is no indication of how many preschool or primary school children of each economic status participated in the study. Furthermore, there is no indication of how the level of consumption of sugar-sweetened beverages by the populations studied has been assessed.

“The authors have importantly highlighted that there are limitations to the interpretation of their study, which only shows an association rather than a causal link,” Steenson adds.

Tackling poverty to improve diets
Sanders points out that children from poorer households are most likely to become obese, as observed by the COVID-19 pandemic and an increase among boys rather than girls. 

“There are lessons to be learned from the pandemic, as well as continuing to discourage the consumption of sugar-sweetened beverages and sweets. Wider recognition should be given to foods that make a bigger contribution to excess calorie intake in children. Tackling poverty, however, is probably the best way to improve the diets of socially deprived children,” Sanders says.

“Children receive hundreds of signals every day encouraging them to snack and eat less healthy food,” Sustain argues.Recently, Susan Webb, chairwoman at the Food and Safety Authority, said in a statement that bringing cake to office spaces is as harmful to one's colleagues as passive smoking, as many people would not eat cake during the day at the office, and stressing the importance of a “supportive environment.”

“Every parent wants their child to grow up healthy, and while it ought to be easy, it isn’t. From misleading health claims and child-friendly cartoons on packaging, to streams of online and TV advertising online, on the street just about everywhere children go, to price and promotions on junk food, influencers and sporting activities promoting fizzy drinks, chocolate and takeaways, children receive hundreds of signals every day encouraging them to snack and eat less healthy food,” Sustain explains.

“The advertising industry spends hundreds of millions of pounds advertising junk food to us each year, and healthy eating campaigns just can’t compete with that. The most important thing the government can do to support parents is to create regulations and business incentives that turn the tide on this constant marketing stream.”

Beyond the sugar levy
Sustain asserts that the government should build on the sugar levy’s success. 

“The National Food Strategy proposed an industry-level reformulation levy on the total volumes of salt and sugar purchased for manufacturing all types of food as an incentive to reduce levels across their product ranges. Another model might see a more targeted levy on specific product categories contributing the highest calories, salt, sugar or saturated fat to diets, but of low overall nutritional value.”

“We believe that such measures would incentivize food companies to innovate faster to make products healthier,” Sustain concludes.

By Beatrice Wihlander