Carbonated water seems as benign as the bubbles rising in the glass, but is it?
For perspective, consider the apple: an apple also looks healthy. “An apple a day keeps the doctor away,” goes the saying. But bake it into a buttery crisp or tart topped with scoops of ice cream, chunks of toffee and a caramel drizzle, and you’ve suddenly turned that sinless apple into a sugary saturated fat dessert from hell.
Likewise, not all carbonated water concoctions are healthy. Soda is carbonated water, after all, but cut with high fructose corn syrup, brominated vegetable oil, often caffeine, and either caramel coloring or, in the case of orange soda, yellow 6 and red 40.
Okay, that’s an extreme example. While much less bastardized than cola, sparkling water flavored with fruit essence may also not be the ideal drink for a health-conscious person like you. And that begs the question…
What is carbonated water anyway?
Basically, carbonated water is just sparkling water. Technically, the H2O is infused with CO2, the same carbon dioxide you exhale.
The book Trends in Non-Alcoholic Beverages, 2020 explains it simply as dissolving cold CO2 gas in water under high pressure. This bubble dynamic turns ordinary water into carbonated water, also known as carbonated water, club soda, seltzer, soda water, etc. When the gas naturally dissolves in water underground in wells and springs, it is called sparkling water and contains minerals such as sodium. and calcium. (Think Perrier mineral water or San Pellegrino.)
Otherwise, CO2 will be pumped in through an industrial process at a beverage factory or through the soda maker on your bar or counter. Add sugar, food coloring and other stuff and you get Coca-Cola and its cousins. Tonic water is another type of carbonated water, but with bitter quinine and high fructose corn syrup added, making your double shot of gin and tonic about 150 calories.
Consumers’ desire to avoid those sugary, high-calorie sodas has made seltzers and sparkling water all the rage, dieticians we spoke to say. According to Future Market Insights, the market for these purportedly healthier bottled beverages is expected to grow to $93.6 billion by 2033. Given America’s obesity crisis and the number of diabetics exceeding 37 million (97 million adults have prediabetes, according to the American Diabetes Association), most experts welcome those trends.
8 Side Effects of Drinking Carbonated Water
1. You improve hydration
“Pure, plain carbonated water is still water and can help you stay hydrated, especially if you struggle to drink enough plain water throughout the day,” says Lauren Manaker, MS, RDNauthor of The Cookbook for First Time Mommy’s Pregnancy And Nurturing Male Fertility.
“There is no scientific evidence that carbonated water is bad for you,” says registered dietitian Mary Wirtz, MS, RDN, CSSD, a board-certified sports dietitian and consultant for Mom Loves Best. “I support individuals who drink carbonated water to increase basic hydration levels. Most women should consume 11.5 cups of hydrating drinks daily, while men should aim for 15.5 cups, according to the National Academies of Sciences, Engineering and Medicine. This can be daunting, but carbonated water, among other beverages, can make this goal more achievable.”
2. You may enjoy drinking water more
The effervescence of carbonated water makes it seem more pleasant than drinking plain water. Added flavors do the same. “
They won’t bore you,” says Katherine Gomez, RD, a registered dietitian with clinical and research experience who is also a medical reviewer for PsycheMag. “Carbonated water comes in a variety of very satisfying flavors, and we often crave more and more.”
Of course, you can always squeeze a lemon into plain sparkling water or add fresh or frozen fruit slices for flavor.
3. It can make your belly bloat
When you drink carbonated water, you swallow more air than you normally would by eating or drinking anything else because of the CO2 contained in the water.
“Those bubbles can cause bloating, which can be uncomfortable,” says Manaker. “This can be especially tricky for people who suffer from irritable bowel syndrome (IBS).”
The effervescent stimulation in the gut can cause constipation or loose stools. On the other hand, the bubbling expansion in your stomach can result in a calorie-free feeling of fullness. One study compared the effect of carbonated water to the influence of still water on feelings of hunger and satiety in a small group of young women. Researchers found that increased satiety and decreased hunger pangs only occurred when the women consumed the carbonated water.
4. You can gain weight
A few studies suggest that carbonated water — with or without artificial sweeteners — can lead to weight gain and a greater body mass index, even though it may contain zero calories. How come?
First, “artificial sweeteners can have negative effects on digestion and blood sugar control, as well as serious health side effects,” notes the registered dietitian nutritionist. Mary Sabat, MS, RDNowner of Body Design by Mary.
For example, research published in 2014 in Nature showed that non-nutritive sweeteners altered the gut microbiome of both mice and humans and may negatively impact metabolism and glucose response. And a meta-analysis of observational studies published in the Journal of the Canadian Medical Association linked non-nutritive sweeteners to weight gain and waist circumference, and higher incidences of obesity, hypertension, metabolic syndrome, type 2 diabetes, and cardiovascular events.
But even those harmless bubbles in pure, unadulterated sparkling water can play a role in weight gain. Small experiments on rats and humans published in 2017 in Obesity research and clinical practice suggest that the fizz caused by the carbon dioxide in drinks triggers the release of the so-called hunger hormone ghrelin, which can lead to overeating.
5. You can lose weight
Zero-calorie diet soda is essentially carbonated water with food coloring and an artificial sweetener added. It has been used in place of sugar-sweetened drinks by millions of dieters for decades, and some studies have shown its effectiveness in reducing body weight. While little research has been done on pure sparkling water, zero-calorie carbonated water with no added colors and artificial sweeteners may work in the same way as no- and low-calorie artificially sweetened drinks.
“As a substitute for sugary drinks, carbonated water can help reduce your calorie intake and support your weight loss efforts,” says registered dietitian Barbara Kovalenko, RDand nutrition advisor at the weight loss app Lasta.
6. It can affect your teeth
Not to the extent that drinking a lot of soda will, but yes, unsweetened carbonated water can contribute to cavities.
“Carbonated water can have a lower pH than regular still water, and that lower pH can erode tooth enamel over time,” says Manaker.
Acidic drinks such as fruit juice, sugary sodas and even sparkling water, especially those with citrus flavors, can dissolve the minerals in our teeth, according to a study recently published in the Journal of the American Dental Association (JADA). Related research in JADA Foundational Science found that dentin, the area under the enamel that protects nerves, is particularly susceptible to erosion from sugar-free carbonated water.
7. It can make you more alert
When the summer sun is out and you’re sweating, a sip of plain water or sparkling water will rehydrate you. But if you want to stay alert and avoid heat-related drowsiness, go for bubbly. In a 2022 experiment reported in the journal Physiological behavior, researchers gave healthy young adults cold carbonated or cold non-carbonated water in a stressfully hot environment. Their analysis found that the carbonated water caused an increase in cerebral blood flow and blood pressure and produced greater feelings of motivation and arousal compared to plain water.
8. Some can cause health problems
According to a 2020 Consumer Reports study, some seltzers and carbonated water contain potentially unhealthy levels of synthetic PFAS chemicals that have been linked to a variety of health problems.
“Many popular beverage brands contain these chemicals known as per- and polyfluoroalkyl substances (PFAS),” says Trista Best, MPH, RD, LD, a registered dietitian for Balance Once Supplements. “These man-made chemicals that are often used in food packaging are sometimes referred to as ‘forever chemicals’ because they are difficult to break down in the body or in the environment.”
Epidemiological studies suggest possible associations between PFAS exposure and liver disease, altered immune and thyroid function, insulin dysregulation, kidney disease and some cancers. The Environmental Protection Agency recommends limiting PFASs in bottled water to 70 parts per trillion (ppt), but each state can set its own standards with some as low as 12 ppt. Some experts argue that less than 1 ppt is acceptable.
So, is carbonated water actually bad for you? The verdict
There is very little evidence that drinking carbonated water poses a risk to your health.
“Overall, it’s not bad for you and may even have some potential health benefits,” says Sabat. “Carbonated water can help keep you hydrated because it contains the same amount of electrolytes as regular water.”
While it can cause bloating, some people find it relieves indigestion and reduces gas discomfort. Drinking carbonated water can keep you from overeating (and help you lose weight) thanks to its satiating bubbles and water volume, as long as your drink doesn’t contain 12 teaspoons of sugar like most fizzy sodas. And those citrus-flavored seltzers — even the fizzy water you squeeze lemons, limes, and oranges into to add flavor — probably won’t rot your teeth unless you drink a lot of them every day. Even then, you can reduce the risk by simply rinsing your mouth with water after drinking a glass to neutralize the acids.
The bottom line: “Carbonated drinks can serve a great purpose for your health, but the kind you choose should be carefully considered,” says Best.
And when in doubt, you can’t go wrong by choosing that childhood sports drink: cold, refreshing water from the garden hose.
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