If you’re concerned about your general and dental health, you may be aware of the need to stay hydrated to support both oral and general health, which are inextricably intertwined in terms of hydration. In terms of general hydration, doctors recommend about 2 litres of water, daily, for the average Australian. For athletes and some other Australians, a substantially larger amount is recommended.

But staying hydrated is not always easy, and sometimes it can be downright boring. After you’ve had four glass of plain water, you may not be thirsty for more. And after two litres is down the hatch? You may never want water again!

This is why sometimes people get tired of plain water and look for something a bit more exciting, or perhaps a bit of variety. And sometimes they choose sparkling water. But you may also have read that carbonated water has a reputation for damaging teeth and harming oral health.

So, how does one balance the need for hydration, oral health, and the desire to drink more than just plain water?  Here are six points to consider.

1) The importance of hydration

Water comprises 60 per cent of the average human body and an astonishing 73 per cent of the brain. If you don’t get enough water, you run the risk of turning your body and brain into the human equivalent of jerky! Water is a key component of health as, among many other things, fluids convey nutrients throughout the body, flush bacteria and other waste products, and keep elimination regular. As we age, we tend to drink fewer fluids and Dr Julian Seifter, an associate professor at Harvard, notes, “That could be a problem if they’re on a medication that may cause fluid loss, such as a diuretic”. The fact is, we all need water, and sparkling water is one way to get it. Sparkling water is one way to increase your hydration level.

2) What is sparkling water?

Plain sparkling water, if there is no added sugar, salt, or flavouring, is simply water that has been carbonated to give it bubbles. Carbonation is achieved by dissolving pressurised carbon dioxide gas into the water. But it’s here that things may begin to turn. A dental threat comes from carbonic acid, which results from carbon dioxide being pressurised into sparkling water. If you’re interested in the science of this, here’s the chemical reaction: H₂O(l) + CO₂(g) ⇌ H₂CO₃. We know, very complicated!

Carbonic acid gives that tingly feeling carbonated drinks. Some studies have suggested that carbonic acid can have a mild corrosive effect on your teeth over an extended period.  What’s important here is the relative pH of your body, and what you put into it to change that pH. Let’s take a look.

3) The importance of pH

If something has a low pH, it is acidic. Drinks with a low pH can lead to dental problems, beginning with eroded enamel. Enamel, the hard, outer layer of  teeth, does not grow back if it erodes.

When enamel erodes, the dentin beneath is exposed and becomes vulnerable to tooth sensitivity and cavities. This can also cause tooth discolouration.

The important number is the natural pH of the mouth, which comes in at about 7.4. As pH drops from that level, liquids become increasingly threatening to your teeth.

Here’s a look at pH of some popular drinks:

• Natural water has a pH of 7
• Bottled water has a pH from 5-7
• Sparkling water ranges from 3-5
• Sodas can be as low as 2 – 2.5

Basically, the higher the pH, the better for your oral health, and you can see that sparkling water is a little low. But, in many cases, low pH is not the biggest threat to your oral health, instead it is what is added to drinks that makes them dangerous.

4) The threat of sugar and other flavourings

The game is entirely changed when sugar and other flavourings are added to sparkling water. The danger sugar represents, to teeth, is well known. Sugar is the preferred food of the bacteria that cause plaque, tartar, gum disease, and tooth decay. If you drink sugared sparkling water, it is no different than drinking a soft drink. Other flavourings, particularly citrusy ones, have lower pH, often driving it down to 5 and lower. Always read the labels of your sparkling water, to be sure that carbon dioxide is the only thing that has been added.

5) What does science say?

A study in the Journal of the American Dental Association took pH measurements of some 400 beverages, including sodas, sports drinks, teas, juices, and sparkling water. The outcome for sparkling water was relatively benign, with the study determining that their pH levels were, at worst, “minimally erosive.”

A study from the Journal of Oral Rehabilitation concluded that most flavourless sparkling water an mineral waters do very little damage. The scientific consensus seems to be that sparkling water may present a theoretical threat to teeth, but outside of a laboratory and very intense experimentation, it is unlikely to harm your teeth. In real life, it’s unlikely you’d drink enough to do any real harm to your teeth.

6) So, is it safe?

Not completely, but there are a few things you can do to reduce its already small risk, and these tactics are actually helpful for drinking any beverage other than plain water:

• Use a straw. This keeps liquid off the teeth
• Drink with a meal.  Chewing increases saliva production, neutralising the effect of acid.
• Drink it plain. Avoid  added sugars, flavourings, and even that wedge of fresh lemon or lime
• Follow it with water. Drinking plain water rinses the teeth.
• Wait 30-40 minutes before brushing.  After drinking or eating, tooth enamel is slightly weakened. So wait to brush.
• And of course, visit your dentist for checkups and cleanings!

In balance, and good health is all about balance, sparkling water is about as safe and healthy an alternative to H2O as can be found.