With diet sodas gaining attention this year, there's no shortage of carbonated drinks to choose from. But soft drinks are packed with sugar and acidity that can erode tooth enamel — and while diet sodas are slightly less harmful, they offer little nutritional value. If you're not ready to give up carbonated beverages entirely, a new study suggests that sparkling water may be a tooth-friendlier alternative.

How sparkling water affects your teeth

Soft drinks damage enamel because they drastically lower the mouth's pH. When the mouth's pH drops below 5.5, tooth enamel begins to dissolve. While sparkling water temporarily lowers pH, the effect is significantly less pronounced than with soda.

"Many people are switching from soda to sparkling water, and our findings suggest that unsweetened sparkling water may be a lower-risk alternative to soda, when consumed in moderation and alongside good oral hygiene practices," explains Wajiha Zulfiqar, a nutrition science student at Purdue University who presented the research.

The study, conducted by the American Society for Nutrition, had 20 adults drink regular soda, regular sparkling water, calcium-fortified sparkling water, and still water. Each participant drank all four beverages, and researchers measured the effect on their salivary pH.

Key findings:

• Regular soda produced the most mouth acidity (lowest salivary pH) compared to both types of sparkling water and still water

• Both regular and calcium-fortified sparkling water caused a temporary drop in salivary pH, with calcium-fortified water showing a dip around the five-minute mark

• pH returned to normal within 20 minutes for both types of sparkling water

• While frequency, timespan, and sugar content all influence the effects of sparkling water, dental erosion appeared significantly less than with traditional soda

The case for drinking sparkling water instead of soda

Drinking soda in moderation typically doesn't cause long-term health issues, but unsweetened sparkling water is a much healthier alternative for those hoping to curb their soda habits.

"Our results suggest that replacing sugar-sweetened sodas with unsweetened sparkling water may help lower the risk of enamel erosion," Zulfiqar says. "The results also highlight an opportunity for the beverage industry to explore reformulation strategies that could potentially reduce the erosive potential of acidic beverages."

What this means for you

If you want to give up traditional sodas but still crave something fizzy, unsweetened sparkling water is a better choice than sugary soft drinks. For the best protection:

• Choose unsweetened sparkling water over flavoured versions with added sugar or acids

• Consume in moderation — even sparkling water temporarily lowers mouth pH

• Maintain good oral hygiene — brush twice daily and wait at least 30 minutes after drinking acidic beverages before brushing

• Consider calcium-fortified sparkling water as an option (though the pH drop returned to normal within the same timeframe)

The bottom line: Reaching for that can of plain sparkling water is a smarter choice for your teeth than sugar-sweetened soda. Just remember to drink it mindfully and keep up with your regular brushing routine.