Sugar tax may prevent millions of dental procedures, study suggests

With oral diseases affecting about 3.5 billion people across the globe, health experts have yet again thrown their support behind a proposed 20 per cent tax on sugary drinks, which they say may have a significant effect on improving the oral health of Australians.A new Australian study, published today in BMJ Public Health, suggests the tax on soft drinks and most juices could prevent 3.7 million cases of tooth decay, 191,000 cases of gum disease, and 115,000 cases of complete tooth loss nationally over the next 25 years.Lead author and Griffith University research fellow Mishel Shahid said it was the first Australian study to quantify the impacts of a proposed sugar tax beyond tooth decay."Obviously we're not saying that a sugar tax would solve all [dental] problems, but it definitely has a big impact," Dr Shahid said.With nearly one in three Australians aged 15 years and above living with untreated tooth decay or cavities, Dr Shahid said the study highlighted "significant" oral health benefits of the proposed tax."Most of the debate that we've seen around sugar taxes has focused primarily on obesity and diabetes," she said. "What we wanted to do was to also look at what impact such a tax would have on the mouth, which is often siloed from the body."The research suggests millions of dental procedures may be prevented under a 20 per cent sugar tax. (Pexels: Elizabeth Lizzie)Dr Shahid suggested any money gained from a proposed tax should be used to strengthen oral health services in Australia, making trips to the dentist cheaper and more accessible.Ten years of sugar tax debateThe proposal of a tax on sugar-sweetened beverages is not new.Ten years ago, a report from the World Health Organization (WHO) suggested a 20 per cent tax on sugary drinks would lower consumption and reduce obesity, type 2 diabetes and tooth decay. Since the report's release, about 115 countries, including Mexico and Hungary, have introduced sugar taxes and the United Kingdom has a similar levy on high-sugar drinks.In 2018, a parliamentary report into Australia's obesity epidemic recommended the government introduce a tax on sugar-sweetened beverages, finding that the "vast majority" of submissions — with the exception of the food and beverage industry — supported the idea.At the time, Coca-Cola Amatil and other submitters claimed there was very little evidence that taxes targeting sugar-sweetened beverages would reduce obesity rates.However, Australia did not introduce a tax on sugar-sweetened drinks following the recommendation, nor in subsequent years when health professionals called for one.In 2024, the Australian Beverages Council, the peak body for non-alcoholic drinks, described the push to introduce a sugar tax as "illogical" and a "revenue raiser", claiming there was very little evidence that they worked and would add financial pressure to struggling Australian families. Australian Dental Association vice-president and practising dentist Angie Nilsson, who did not contribute to the study, said Australia was "behind the times"."We've got great evidence from the UK that shows that after a sugary drinks levy, people reduced their consumption," Dr Nilsson said."On top of that, there's been evidence that there has been a reduction in people presenting to hospitals with preventable admissions for oral health diseases."Dr Nilsson said this new study built on existing research to show the potential oral benefits of a sugar tax."Whilst it's not surprising, it certainly adds to the body of evidence to show that sugars in Western modern-day diets need to be reduced somehow," she said.But she also pointed out the study did not include energy drinks, which she considered one of the "worst offenders".Therefore, Dr Nilsson said, the true benefit of a sugar tax could be even more significant than suggested.Modelling from 2021 by the Australian Medical Association, which has long lobbied for a similar tax, suggested a 20 per cent tax hike on sugar-sweetened drinks might result in 16,000 fewer cases of type 2 diabetes, 4,400 fewer cases of heart disease and 1,100 fewer cases of stroke over a 25-year period.Health Minister Mark Butler has been contacted for comment.Modelling dental and health benefitsTo understand the impact of a sugar tax, the researchers looked at two scenarios, one with no sugar tax and a second following the introduction of a 20 per cent tax on sugar-sweetened drinks."The difference between those outcomes helps us quantify the impact of the tax," Dr Shahid said.The projections were modelled off Australia's 2019 population, using estimates from the Global Burden of Disease 2019 study to predict dental outcomes over a 25-year period.Tasman Davies, PhD candidate at the George Institute for Global Health who did not contribute to the study, said the potential dental benefits of a sugar tax could be seen after just one year, with significant improvement noted after five."The reduction in dental caries [tooth decay] would be fully seen in five years," he said."Whereas the argument for diabetes and heart diseases is very important to consider, but that takes a lot longer to see improvements in those health outcomes."Dr Nilsson said, from an oral health perspective, reducing sugar intake had a positive impact in just a few weeks."But it's also not just the sugar; sweet beverages also carry that acidic content that has compounded with causing tooth decay and other diseases," she said.A separate Australian study, published in April in The Lancet Public Health, modelled the potential health benefits of a 20 per cent tax on unhealthy food such as confectionery, chips, ice cream as well as a 20 per cent subsidy on fruits and vegetables.It found these measures could prevent 212,000 premature deaths in Australia and save $14.9 billion in health-care costs over the lifetimes of adults alive today."A broader tax on unhealthy foods could have around seven times the health benefits as a tax on sugary drinks alone," said Mr Davies, the lead author of the study published in The Lancet in April."It could also be orders-of-magnitude more powerful than other food policies such as mandating the health-star rating or restricting advertising or educational campaigns."Mr Davis's study suggested using the income generated from the tax to offset the subsidy on fresh fruit and vegetables.Sugar audit shows scale of problemAn audit from the Food for Health Alliance, published last week, found that some drinks sold in Australian supermarkets had up to 2.5 times the daily limit of sugar recommended for good health.Some 600ml soft drinks contained about 16 teaspoons of sugar and large cans of energy drinks had about 13 teaspoons of sugar in them.WHO recommends adults consume no more than 12 teaspoons of free sugar a day, and ideally limit consumption to six teaspoons.Jane Martin, executive manager of the Food for Health Alliance, said sugary drinks were the biggest contributor to sugar consumption in Australian diets, making up a quarter of total sugar intake.“Sugar content in Australian drinks is not decreasing as much as it should be because we are not incentivising action through a tax based on the amount of sugar in these drinks," she said. She wants Australia to introduce a tiered sugary drinks tax paid for by companies, similar to the UK's soft drinks levy.Dr Nilsson said a sugar tax would either change consumer behaviour, with the higher price convincing them to make a different choice, or force manufacturers to rethink their formula.After the UK introduced a sugar levy, some drinks manufacturers voluntarily reformulated their products to avoid the tax, which made them healthier for people to consume.Angie Nilsson wants a tax on sugar-sweetened beverages to be introduced in Australia. (Supplied: Australian Dental Association)With soft drinks often priced similarly to bottled water, Dr Nilsson said it was "too easy" for Australians to access them.But Mr Davies said his study showed that for maximum impact, there needed to be a "two-pronged approach" where a tax was introduced for sugary drinks and healthier choices were subsided to make them cheaper.Often, he said, junk food was cheaper and more convenient than healthier choices, which made it challenging for families on lower incomes to eat well."If we look over the past 50 years, food products look very different," he said. "At least half of the food that we eat [today] is what's called ultra-processed. "In the food system, things are stacked against us. Unhealthy foods have highly prevalent advertisements, and so a policy like taxation can help counteract those forces that push us towards unhealthy foods."