Sugary drinks tax may be effective in preventing childhood obesity

A sugary drinks tax in England was associated with a decreased prevalence of obesity among older primary school children, according to new research from the University of Cambridge.

The study estimates that approximately 5,000 yearly cases of obesity may have been avoided in year six girls (10 to 11 years old) with the introduction of the Soft Drinks Industry Levy.

However, investigators found no significant associations between the tax and obesity levels in year six boys or younger children from the reception class (4 to 5 years old).

“We urgently need to find ways to tackle the increasing numbers of children living with obesity, otherwise we risk our children growing up to face significant health problems,” said the study’s first investigator Nina T. Rogers, PhD, MRC Epidemiology Unit, University of Cambridge School of Clinical Medicine, Institute of Metabolic Science. “That was one reason why the UK’s soft drinks industry level was introduced, and the evidence so far is promising. We’ve shown for the first time that it is likely to have helped prevent thousands of children each year becoming obese.”

A global health problem, children who are obese are more likely to suffer from serious health problems including high blood pressure, type II diabetes, and depression in childhood and in later life. One in ten reception aged children in England is living with obesity and the figure doubles to one in five children in year six.

According to the UK-based investigators, young people consume significantly more added sugars than recommended, a large source of which is sugar-sweetened drinks. Children in deprived households are more likely to be at risk of obesity and to be heavy consumers of sugar-sweetened drinks.

The UK governments introduced a two-tier sugar tax on soft drinks in April 2018 to protect children from excessive sugar consumption and address childhood obesity. This tax was aimed at manufacturers of the drinks to incentivize a reduction in the sugar content of soft drinks.

Investigators from the Medical Research Council (MRC) Epidemiology Unit at the University of Cambridge tracked changes in the level of obesity in children in England in reception year and year six between 2014 and 2020. They compared changes in levels of obesity 19 months after the sugar tax was introduced, taking into account previous trends in obesity levels.

The findings show the introduction of the sugar tax was associated with an 8% relative reduction in obesity levels in year six girls, which was equivalent to the prevention of 5,234 cases of obesity per year in just this group. These reductions were greatest in girls whose schools were in deprived areas, with a 9% reduction.

The study observed no associations between the sugar tax being introduced and changes in obesity levels in children from the reception class. No overall change in obesity prevalence was observed in year six boys.

Despite finding an association and not a causal link, investigators say the study adds to previous findings that the tax was associated with a substantial reduction in the amount of sugar in soft drinks.

“It isn’t a straightforward picture, though, as it was mainly older girls who benefited,” Rogers said. “But the fact that we saw the biggest difference among girls from areas of high deprivation is important and is a step towards reducing the health inequalities they face.”

The study, “Associations between trajectories of obesity prevalence in English primary school children and the UK soft drinks industry levy: An interrupted time series analysis of surveillance data,” was published in PLOS Medicine.

This article was published by our sister publication HCP Live.