A tax on sugar in soft drinks will prevent tens of thousands of people from becoming dangerously overweight but the obesity crisis will only be solved by a range of measures, including action to reduce sales of sweets and chocolates, experts said.
The soft drinks levy could potentially save up to 144,000 adults and children from obesity every year, prevent 19,000 cases of diabetes and avoid 270,000 decayed teeth in the best scenario, scientists at Oxford University found.
But while the sugar tax is an important step towards defeating obesity, it is not the whole story, said Susan Jebb, professor of diet and population health at the University of Oxford, who is one of the authors of the study. “If we’re saying we really, really need to get a grip on sugar intake, the next place we would go is confectionery,” she said.
“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.
“Then, once this bill is passed, we need to consider how to take effective action to reduce other sources of sugar in children’s diets, notably confectionery, which has so far been relatively overlooked while hearts and minds have been focused on the soft drinks levy.”
Confectionery is a discretionary item, which we might enjoy but do not need, said Jebb. “The whole philosophy of sweets as treats – we need to think hard about that,” she said.
The academics, writing in the Lancet Public Health journal, used modelling to determine what sort of impact the soft drinks levy would have. There are many variables: one is the two bands, with a lower levy for drinks with 5-8g of sugar per 100ml and higher for those with more than 8g per 100ml.
The biggest impact will come if manufacturers change their recipes, cutting the amount of sugar in their drinks to avoid the levy altogether. If they decide to pass on the tax as a hike in price, there will still be positive but smaller health gains.
The design of the tax is unique, said Adam Briggs and colleagues who wrote the paper, because it is imposed on company profits, not sales as in other countries such as Mexico. That puts pressure on companies to reformulate their products.
Some, such as Lipton’s Ice Tea, Sprite and all of Tesco’s own-brand soft drinks, have already responded by cutting the sugar content. Other companies have made clear their hostility to the levy. Coca Cola called it disappointing and told the Guardian it would announce its intentions in the new year. Recently it has said it intended to continue to grow the market for its low-sugar alternatives to its high-sugar drinks.
The paper looked at three possible responses to the levy by industry: reformulation, price increases to the consumer, and a change in companies’ marketing to focus on low, rather than high-sugar products. It considered the effects on obesity, diabetes and tooth decay – the last of which is the main reason for admission of children to hospital.
If companies hike their prices by up to 20%, there will still be health gains, although not as much as for reformulation. That would reduce the numbers of obese adults and children by 81,600 and result in 10,800 fewer cases of diabetes and 149,000 fewer decayed teeth per year.
Children at risk of obesity would benefit most – and boys more than girls, because they drink more sugary drinks. In the best-case scenario, after reformulation, there would be 61,000 fewer obese boys and 34,000 fewer obese girls under 18 every year. However adults would be protected from diabetes in far larger numbers than children.
The British Soft Drinks Association was unimpressed with the study. “The problem with this modelling is that it is based on the flawed concept that obesity can simply be attributed to calorie or sugar intake per se and consumption of one product in particular, rather than overall lifestyle and diet,” said Gavin Partington, the BSDA director general. “This error is plain to see given that sugar intake from soft drinks has been declining for several years now, down 17% since 2012. There is no evidence worldwide that a tax on soft drinks has had an impact on levels of obesity.”
The research suggests that the sugar levy will only cut the nation’s calorie intake by 5 kcal a day - the equivalent of four sultanas – said Tom Sanders, professor emeritus of nutrition and dietetics at King’s College London. “This is a very small reduction in energy intake – equivalent to the amount of energy expended by one minute of brisk walking,” he said, adding that he found some of the predictions about improvements in health “hard to swallow”.
But the Obesity Health Alliance, representing over 30 health organisations, said: “We’ve always believed the soft drinks industry levy will deliver positive health benefits, so it’s great to see even more evidence supporting this.”
