Due to begin in April 2018, the tax corresponds to the sugar content of drinks: drinks with five to eight grams of sugar per 100 milliliters will have a low tax, while drinks over eight grams of sugar per 100 ml will feature a high duty. Drinks with less than five grams of sugar per 100 ml will not be taxed.
In the first study to estimate the tax’s health impact, researchers created models that calculated how three likely industry reactions to the levy could affect the health outcomes of British residents. Their findings were published Thursday in the journal The Lancet Public Health.
“The good news is that our study suggests that all of the most likely industry responses to the tax including reducing sugar content of soft drinks, raising prices of high-sugar drinks and increasing the market share of low-sugar drinks have the potential to improve health by reducing rates of obesity, diabetes and tooth decay,” said lead author Adam Briggs.
The models estimate that the soda industry reducing the sugar content of their high-sugar products by 30 percent, in addition to a 15 percent reduction in mid-sugar drinks, could result in 144,000 fewer British residents with obesity, 269,000 fewer teeth decaying annually, and 19,000 fewer cases of type 2 diabetes per year.
If the industry responds by increasing the prices of high and mid-sugar drinks by up to 20 percent, the team estimates the number of adults and children with obesity will be reduced by 81,600, along with 149,000 fewer cases of tooth decay. There would also be 10,800 fewer cases of type 2 diabetes.
“In spite of the uncertainties, the direction of the effect is clear: this levy will have a positive impact, especially on children’s health. Of course, on its own a soft drinks levy cannot solve the obesity crisis, but we should not underestimate the importance of this step, both for the UK and as a case study for other parts of the world,” co-author and University of Oxford professor Susan Jebb said.
The authors predict that children will likely benefit the most from industry responses to the tax, while fewer cases of tooth decay will probably be the first noticeable positive health outcome among British residents.
However, if companies increase the prices of their products – including products with low sugar or no sugar – or introduce marketing campaigns to lead consumers to switch from low to mid-sugar drinks, the tax would fail to achieve the positive health outcomes predicted in the team’s model.
“The extent of the health benefits of the tax will depend on industry’s response,” Briggs said. “We must therefore be vigilant to ensure the food industry acts to remove sugar from soft drinks, and that where the tax is passed on to consumers it increases the price of targeted products only – drinks with high levels of sugar.”
The authors acknowledge the industry will likely use a combination of approaches to protect profits, and caution that there is a high level of uncertainty in the estimates – though the projections do provide evidence of how different responses from companies can produce varying degrees of health benefits.
Lennert Veerman – a lecturer from the school of public health at the University of Queensland, Australia – said while the ultimate impact of the tax on public health will take years to determine, he thinks the levy could be even more beneficial than the team estimates. Veerman was not involved in the study.
“Future work can assess the impact of sugar-sweetened beverages (SSB) taxes on chronic diseases that would materialize later in time, such as heart disease, stroke, low back pain, and osteoarthritis, which would further strengthen the case for the SSB tax. The health impact of the tax on sugared drinks proposed in the U.K. is likely to be substantial and considerably greater than Briggs and colleagues suggest,” he said.
Several U.S. cities have implemented sugary drink taxes, including Oakland, San Francisco, Albany, California, and Boulder, Colorado, which passed such measures in November.