Myth or Fact: Does Seltzer Water Dehydrate You?

Whether you call it seltzer, sparkling water, or soda water, this drink has a following that can not be stopped. In 2017, $1.8 billion worth of this fizzy drink was sold worldwide. In the U.S., La Croix, one of the most popular sparkling water brands, grew by 65% in the 2017 fiscal year alone. 

On the health front, seltzer water has a lot going for it. The Centers for Disease Control says a glass of sparkling water is a significantly better option than a calorie-laden soda.  

But it’s not all good news for water-based carbonated beverages. A number of rumors are floating around the internet about what seltzer water can and can’t do – and some have a hint of truth behind them. Let’s dispel the myths and explain the truths when it comes to the world of hydration and seltzer water.

What is Seltzer Water? 

Seltzer water is the simplest version of carbonated water. The beverage is made by combining regular water with carbon dioxide gas. However, this results in just bubbly water with no additional taste. To make the drink more appealing, manufacturers often add natural and artificial flavorings. An example of seltzer water with added flavor would be La Croix, the soda brand that has so exploded in popularity in recent years. 

In order to make a few things clear, let’s go over how seltzer water differs from club soda, sparkling mineral water, tonic, and tap water. 

Tap Water 

The most obvious option on this list, tap water is the regular water that comes from the faucet in your home. Nothing is added to this, and it does not have to be purchased specially made or with added flavors. However, flavor concentration packets like Mio or, ahem, a certain rapid hydration mix, can amp up the flavor and help people drink more water.

Are you concerned about your own hydration levels? Take the quiz below to find the best Hydrant for your hydration routine.

Club Soda

Think of club soda as being “seltzer water plus.” That’s because club soda is a carbonated beverage to which sodium bicarbonate, sodium citrate, disodium phosphate, and—occasionally—sodium chloride are added. These salts neutralize the acidity of seltzer water. Club soda is often left unflavored. 

Sparkling Mineral Water

Sparkling water is also similar to seltzer water. However, sparkling mineral water is rich in potassium, sodium, and magnesium. Unlike club soda, these additions occur naturally as the water is filtered through underground rock. The bubbles are added artificially. 

Tonic Water

Lastly, tonic water is a mixture of quinine powder, soda, and sugar. The drink started as a treatment for malaria [1]. Quinine powder tastes bitter, doctors needed help in getting people to ingest it, and thus a beverage was born. 

Tonic water comes in regular as well as light for those looking to cut down on calories. (Many people are surprised to learn that tonic water contains more than 120 calories per 12-ounce serving.) 

Seltzer Water Benefits 

Since seltzer water is nothing but regular water with pressurized carbon dioxide added, its benefits are essentially the same as those of water. For example, drinking seltzer water improves hydration levels, which supports healthier skin, better blood pressure, more energy, and all of the other positives that go along with being properly hydrated. 

Does Seltzer Water Dehydrate You?

The myth that seltzer water dehydrates you is just that: a myth.  

No scientific evidence has ever shown sparkling water is not hydrating, or that it will hydrate you any less than regular water.  

However, some claim that people will consume less carbonated water due to bloating, and therefore fall short of their hydration needs. This is why it can be important to drink seltzer water in concert with traditional water and other hydrating beverages. 

Are There Any Other Risks? 

Ok, now let’s address some of those other rumors about sparkling beverages. Here are some of the most pervasive myths about carbonated water, and what science has to say about them.

Is Carbonated Water Bad for Bone Health?

Simply put, no. Carbonated water will not affect bone mineral density [2] any more than traditional water would. This is because, in its case, all seltzer water is, is water. 

However, there is some evidence to say that carbonated water could be bad for tooth enamel [3] in certain cases.

Problems With Carbonic Acid

Carbonic acid is what forms when carbon dioxide dissolves in water. The slight burning or tingling sensation you feel when you drink seltzer water or other carbonated beverages? That’s carbonic acid at work.[4] 

Carbonic acid is, as the name implies, mildly acidic. But consuming a mildly acidic beverage will not make your body more acidic. Your body tightly regulates its internal pH, maintaining a slightly alkaline level between 7.35 and 7.45 by using your kidneys and lungs to remove excess carbon dioxide from the blood.   

So consuming carbonic acid is not problematic for your body. But it can potentially cause issues for your teeth. 

The International Journal of Pediatric Dentistry has said seltzers should be recognized “as potentially acidic drinks rather than water with flavoring.” [5]

Manhattan-based cosmetic dentist Dr. Lee Gause told NBC News that he’s seen some cases where people who have an overly acidic diet—due to a combination of carbonated beverages, sodas and juices and the absense of regular water—wind up with tooth erosion. But he added, “All of that being said, [seltzer] is safe to consume in appropriate volumes — keep it to once a day with meals, at a maximum, and be sure to wash everything down with standard water.” 

Potential problems with Flavors

Citrus flavored La Croix can be as damaging to your teeth as orange juice due to the addition of citric acid to the already acidic mix. The same will be the case for any citrus-flavored beverage. Think orange, lemon, grapefruit, and more.  

For this reason, it is recommended that you stick to non-acidic flavors as much as possible and brush your teeth after drinking any citrus-flavored seltzers, just as you would orange juice after breakfast. 

Seltzer Water vs. Still Water: What’s More Hydrating? 

In summary, seltzer water is almost exactly the same as traditional water. For that reason, they are equally as hydrating. 

The main difference is your comfort. Some people think that the bubbles make it more appealing. Thus, they drink more. In that case, seltzer water would be “more hydrating,” but not because of any chemical difference in the makeup of the drink. 

However, others might feel bloated after drinking too much carbonation, and therefore drink less. In that case, seltzer water would be “less hydrating.” But again, not on a chemical level. 

Both seltzer water and plain water can be part of a healthy approach to hydration. How much of each you drink will be a matter of taste, health, and preference. Try to keep consumption to one can a day and avoid citrus flavors unless you can brush your teeth after consumption.