- A small study found sparkling water briefly increased mouth acidity but much less than sugary soda.
- Mouth pH returned close to normal within 20 minutes after sparkling water.
- For people cutting down on sugary drinks, unsweetened sparkling water looks like a much better option for teeth.
People often worry that sparkling water may damage teeth because it is acidic.
A small preliminary study suggests the answer is more reassuring than many expect.
Researchers compared sugar-sweetened soda, regular sparkling water, calcium-fortified sparkling water and plain water in 20 adults.
They measured salivary pH after each drink.
This is more useful than just measuring the drink itself, because saliva helps neutralise acidity in the mouth.
Tooth enamel can begin to dissolve when pH falls below about 5.5.
In this study, soda caused the biggest and longest drop in mouth pH.
Sparkling water caused a smaller, temporary drop.
Regular sparkling water lowered pH after two minutes, while calcium-fortified sparkling water lowered it after five minutes.
By 20 minutes, pH had returned close to baseline for both sparkling waters.
Importantly, short-term pH stayed above the level usually associated with enamel damage.
That does not mean sparkling water has no effect at all.
Frequency matters.
Sipping acidic drinks all day keeps teeth exposed for longer, even if the drink is sugar-free.
But compared with sugary fizzy drinks, unsweetened sparkling water is clearly the better choice.
For people with diabetes, this is particularly relevant.
Switching from sugary drinks to unsweetened sparkling water can reduce sugar intake and help with glucose control.
It may also protect teeth by removing the combination of sugar and acid that makes standard fizzy drinks such a problem.
The best approach is simple.
Choose unsweetened sparkling water, avoid constant sipping throughout the day and keep up normal brushing and dental care.
If you want flavour, go carefully.
