Sporting a sugar-free label does not make a product tooth-friendly.
Researchers in Melbourne, Australia, tested 23 different types of sugar-free drinks – including soft drinks and sports drinks – and found that those containing acidic additives and those with low pH levels cause measurable damage to tooth enamel, even if they contain no sugar. The studies found that the majority of soft drinks and sports drinks led to softening of dental enamel – the outer layer of the tooth – by between one-third and half.
While most people are probably aware of the link between sugar and tooth decay, what is perhaps less well understood is the nature of that link, and why drinks that are acidic can also be bad for our teeth. Sugar is linked to tooth decay because it forms a plaque on the tooth surface that bacteria digest and convert to acid. The acid attacks teeth by dissolving the outer layers of tooth enamel. Thus, drinks that are acidic – whether they contain sugar or not – can also erode teeth.
The researchers recommend that sugar-free products should carry labels with information that helps consumers to evaluate them in relation to oral health. They suggest that people check for acidic additives, such as citric acid and phosphoric acid, when deciding which sugar-free products to buy. They also suggest that after eating or drinking acidic products, do not brush teeth straight away, as this can remove the softened tooth layer. Instead, rinse the mouth with water and wait for an hour or so before brushing. Chewing sugarless gum after drinking an acidic drink can also help to neutralise the acid. Of course, quenching your thirst with water is the healthiest option.