While the carbonated soda industry has long been booming, bringing in annual revenue to the tune of $328 billion according to Statista, a growing segment within that market is now valued at more than $32 billion − and is projected to reach $93 billion by 2030. 

That rapidly expanding market has been built around seltzer water − a product touted by celebrities and influencers alike. Despite its growing popularity, seltzer water has some known disadvantages and plenty of advantages that consumers might want to be aware of.

What is seltzer water?

Seltzer water, also called sparkling water, carbonated water or bubbly water, "is created when carbon dioxide bubbles are added to still water," says Jamie Bering, MD, a gastroenterologist at Mayo Clinic in Arizona. Indeed, it's the injection of that carbon dioxide gas under pressure "that causes the bubbles and fizzy quality of seltzer water," explain Jen Messer, a nutrition consultant and registered dietitian at Jen Messer Nutrition.

Popular seltzer water brands include La Croix, Perrier and S. Pellegrino. Some people also use sparkling water machines such as SodaStream to make their own carbonated water at home. 

Is seltzer water bad for you?

Though seltzer water is just as hydrating as regular water, it does have some advantages and disadvantages different than drinking tap water alone. Messer says that sparkling water can be "more interesting, appealing and enjoyable than plain water" especially so because it often comes in "a wide variety of flavors." What's more, she says such flavors don't usually require the use of artificial sweeteners, "which makes seltzer water a good choice for those looking to reduce their calorie intake or avoid added sugars." In this way, sparkling water can also be a great way to transition away from soda. "Seltzer water can be used as a healthier alternative to drinking soda," says Bering.

Indeed, a single can of Coca-Cola contains 39 grams of sugar, 14 grams more than the 25 grams of added sugar the American Heart Association recommends women to consume in an entire day and 3 grams more than the 36 grams of sugar it recommends men to stick to daily. Frequent consumption of soda has been linked to obesity, Type 2 diabetes, nutritional deficiencies and an increased risk of heart disease.

What is unhealthy about Diet Coke?And is regular Coca-Cola actually better for you?

Lisa Young, PhD, RDN, an adjunct professor of nutrition at New York University and author of "Finally Full, Finally Slim," says that some people who drink the bubbly liquid "have also found that drinking seltzer water can also provide temporary relief from indigestion." 

But seltzer water has some disadvantages as well. For instance, Messer agrees that many people have reported that seltzer water can help with indigestion, but "interestingly, other individuals have found that seltzer water actually causes gastrointestinal discomfort such as bloating or gas." It can make one's acid reflux worse as well. 

And Messer says the liquid isn't great for anyone trying to reduce sodium in their diets. "Your favorite can of seltzer water may have 100 or 200 milligrams of sodium, which doesn’t seem like much, but it can really add up," she says. That's especially worth keeping in mind for people watching their blood pressure. 

Young says that because seltzer water is also acidic, "high consumption may affect the enamel on teeth over time." In fact, not only can such acidity cause tooth decay, but people who drink a lot of seltzer water may also not be getting as much decay-preventing fluoride as people who drink tap water since fluoride is added to most supplies of drinking water in America.

What happens when you drink seltzer water?

Because of the carbonation in seltzer water, many of the same things happen in one's stomach when it's consumed as happens when drinking soda or other carbonated beverages. When carbonation enters the stomach, our body warms it, and the carbon dioxide gas gets released and expands, which eventually has to come out somewhere − usually through flatulence or burping. 

Many people prefer that side effect over the taste of drinking regular water alone, however, and all the experts agree that seltzer water is preferred over drinking traditional soft drinks. "It's important to note that seltzer water can vary just as people do and some individuals may experience a range of advantages or disadvantages based on their individual health, preferences and consumption habits," explains Messer. "As with any food or beverage, moderation is key, and it's advisable to consult with a healthcare professional if you have specific health concerns."