Diet sodas, 100% citrus fruit juices and other no-sugar-added drinks can be surprisingly bad for your teeth. It's true that consuming beverages that are lower in sugar decreases your risk for tooth decay, but drinking diet or sugar-free beverages doesn't remove the risk entirely.
Most people know that drinking sugary drinks can cause tooth decay, but you also have to watch out for a drink's acidity. The lower the pH of a food or drink, the higher risk for tooth erosion — this includes diet sodas, juices, energy drinks and others.
How Sugar-Free Drinks Hurt Your Teeth
Studies carried out in the Oral Health CRC on sugar-free beverages, sugar-free confectionery and sports drinks demonstrated that "many of these products contained multiple acids and had low pH values." Essentially, many people think that switching from regular to diet soda will keep their teeth healthy. Unfortunately, although they often contain no sugar, diet sodas usually cause about the same amount of dental erosion as regular sodas and can harm your teeth.
Additionally, while the sugar in regular soda and other sweet drinks forms harmful acid in your mouth, diet or sugar-free beverages also contain phosphoric acid, the same found in regular, sugary soda. Citric acid and tartaric acid are just some of the additional ingredients in diet drinks and fruit juices that can damage teeth. As you sip, ongoing acid attacks weaken tooth enamel, causing decay over time, says the Wisconsin Dental Association.