Bubly sparkling water is, by any standard nutritional measure, a perfectly fine drink. It contains zero calories, zero sugar, no artificial sweeteners, and no sodium. Its ingredient list is short: carbonated water and natural flavors. For anyone using it to replace soda, juice, or other sugary drinks, the swap is a clear win. The more interesting question is whether the carbonation itself, the flavoring, or the aluminum can it comes in introduces any downsides worth thinking about. The answer is more layered than the marketing suggests.
What Is Actually in a Can of Bubly
Bubly’s ingredients are carbonated water and “natural flavor.” That is the entire list. There are no added sugars, artificial sweeteners, phosphoric acid, caffeine, or sodium. This puts it in a different category from diet sodas (which contain artificial or non-nutritive sweeteners), regular sodas (loaded with sugar or high-fructose corn syrup), and even some competing sparkling waters that sneak in small amounts of sweetener or sodium. From a macronutrient standpoint, drinking a can of Bubly is essentially drinking water with bubbles and a hint of fruit essence.
The “natural flavor” designation is vague by design. Under FDA regulations, natural flavors can be derived from fruits, vegetables, herbs, spices, or other plant and animal sources. For a product like Bubly, these are typically fruit-derived volatile compounds that give the water its lime, grapefruit, or strawberry taste without contributing calories. The amounts are tiny, and they do not meaningfully change the drink’s nutritional profile. For practical purposes, Bubly is flavored carbonated water and nothing more.
The Dental Question Is Real but Often Overstated
This is where the conversation gets more nuanced. Carbonated water is more acidic than still water because dissolved carbon dioxide forms carbonic acid. Plain unflavored sparkling water typically has a pH around 3.5 to 4.5, which is mildly acidic. Adding fruit flavoring, even without sugar, can push that pH lower. Research on flavored sparkling waters found that all tested products had pH values between 2.74 and 3.34, with erosive potential similar to or greater than pure orange juice in a lab dissolution test.
That sounds alarming, but context matters. Lab studies soak teeth in beverages for hours or days straight, which does not reflect how people actually drink. One study measured significant enamel mass loss in specimens immersed in flavored sparkling water continuously over nine days, with measurable erosion beginning on day one.
In your mouth, saliva constantly buffers acidity and remineralizes enamel. The real-world risk from flavored sparkling water is much lower than what lab conditions suggest, but it is not zero. Sipping acidic drinks slowly over long periods gives acid more contact time with teeth, which is worse than drinking quickly. If you go through several cans of Bubly throughout the day, nursing each one over an hour, you are keeping your mouth in a mildly acidic state for a prolonged stretch. That pattern, repeated over years, could contribute to enamel erosion.
For perspective, sugary and caffeinated drinks cause far more dental damage. A study comparing multiple beverages found that cola, sports drinks, and energy drinks produced significantly more enamel surface roughness than coffee, bottled water, or tap water.
A clinical trial in adolescents also found that bacterial growth in the mouth was dramatically higher after drinking sugar-containing soda (an increase of 310,000 colony-forming units) compared to carbonated water (an increase of 60,000 colony-forming units).
The practical takeaway: Bubly is far gentler on teeth than soda, sports drinks, or juice. But treating it exactly like plain water, especially if you sip it all day, overstates its dental innocence. Drinking it with meals, using a straw, or rinsing with plain water afterward all reduce contact time with enamel.
Carbonation and Your Bones
The idea that carbonated drinks weaken bones is one of the more persistent health myths around sparkling water. It likely stems from older research linking cola consumption to lower bone density, but the culprit there was phosphoric acid, which is found in dark colas but not in sparkling water. Bubly contains no phosphoric acid.
A study of older women found that bone mineral density was not associated with intake of any type of carbonated beverage after adjusting for age, obesity, calcium intake, exercise, and other relevant factors. The researchers concluded that modest intake of carbonated beverages does not appear to have adverse effects on bone density.
Separately, research examining whether carbonation increases calcium loss through urine found that the net effect of carbonated beverage constituents on calcium balance is negligible. The small, transient increase in urinary calcium that caffeine can cause is compensated for later in the day, and since Bubly contains no caffeine, even that minor mechanism does not apply.
If you have been avoiding sparkling water out of bone health concerns, the evidence does not support that worry. The issue was always about what else is in the drink, not the bubbles themselves.
Digestive Effects Cut Both Ways
Carbonation has real effects on your digestive system, but whether those effects are good or bad depends on what is going on with your gut.
On the positive side, a controlled trial found that people with indigestion and constipation who drank carbonated water for two weeks reported significantly lower dyspepsia scores compared to those drinking tap water. Gallbladder emptying also improved in the carbonated water group. For people dealing with sluggish digestion or occasional constipation, sparkling water may genuinely help move things along.
On the other hand, carbonation temporarily lowers the pressure of the valve between your esophagus and stomach and increases the frequency of relaxations in that valve. In healthy subjects, drinking a carbonated beverage roughly halved the resting pressure of that valve compared to baseline and significantly increased relaxation events compared to plain water. Those relaxations are the mechanical trigger for acid reflux. If you already deal with heartburn or gastroesophageal reflux, carbonated drinks of any kind, including unsweetened sparkling water, can make symptoms worse.
Carbonation also changes how food sits in your stomach. One study found that carbonated water did not alter overall gastric emptying speed, but it significantly changed how the meal distributed itself inside the stomach, with more food and liquid retained in the upper portion. That redistribution is what creates the sensation of fullness and bloating that some people feel after drinking sparkling water. It is not dangerous, but it is uncomfortable for some.
Does Carbonation Make You Hungrier
An animal study that got a fair amount of media attention found that rats given carbonated beverages had elevated levels of ghrelin, the hormone that stimulates appetite, and ate more food than control rats. A parallel observation in 20 healthy men showed that ghrelin levels also increased after drinking carbonated beverages compared to flat controls.
This is worth knowing but also worth putting in proportion. The study was small, the human arm was observational rather than a full feeding trial, and measuring a short-term hormone spike does not tell you whether people actually eat more calories over the course of a day or gain weight over time. Ghrelin levels fluctuate naturally throughout the day for many reasons. No long-term human study has linked unsweetened sparkling water consumption to weight gain.
If anything, the fullness and bloating that carbonation can produce might work in the opposite direction for some people, making them feel too full to eat more at a meal. A study measuring stomach volume after carbonated versus non-carbonated beverages found that total gastric volume was significantly higher after the carbonated drink, though the difference did not persist through the meal itself.
Sparkling Water as a Soda Replacement
Where Bubly earns its health credentials most clearly is as a substitute for sugary drinks. A systematic review and meta-analysis of randomized trials found that replacing sugar-sweetened beverages with non-caloric alternatives led to a long-term reduction in BMI. That is a modest but meaningful shift at a population level, and it comes without requiring people to drink plain water, which many find boring.
The psychological dimension matters here. Many people who quit soda find that they miss the fizz more than the sweetness. Sparkling water fills that sensory gap. If a can of Bubly keeps you from reaching for a Coke or a Sprite, the health math is overwhelmingly in Bubly’s favor. The calories, sugar, phosphoric acid, and caffeine you are not consuming add up to real benefits over months and years. The minor downsides of carbonation, like slightly more acidity on your teeth, pale in comparison.
That said, if you are already a plain-water drinker and you are wondering whether switching to Bubly would be an upgrade, the answer is no. Plain still water has no acidity, no can lining to worry about, and no microplastic exposure from carbonation pressure. Bubly is not healthier than water; it is a much healthier alternative to less healthy drinks.
What the Can Itself Contributes
Bubly comes in aluminum cans lined with a thin coating of epoxy resin. That lining prevents the acidic carbonated water from reacting with the aluminum, but it can be a source of bisphenol A (BPA), a chemical that has attracted scrutiny for its potential to mimic estrogen in the body. Research measuring BPA leaching from aluminum cans with epoxy resin linings detected roughly 68 nanograms per container under experimental conditions.
That is a very small amount. Regulatory agencies generally consider the levels of BPA that leach from food and beverage containers to be well below thresholds of concern for most adults. Still, some people prefer to minimize exposure, especially for children or during pregnancy. Many can manufacturers have been transitioning to BPA-free linings, though the replacement chemicals are not always well studied either. If BPA exposure is something you think about, drinking from glass bottles or using a home carbonation system sidesteps the issue entirely.
Microplastics from Carbonated Bottles and Cans
A newer area of research involves microplastics and nanoplastics released into carbonated beverages from their packaging. A 2023 study found that the pressure and bubble action from dissolved CO2 increased the release of micro- and nanoplastics from plastic bottles. Polypropylene bottles released roughly 234 particles per liter under controlled conditions, and that number climbed to about 450 particles per liter after repeated freeze-thaw cycles. Actual commercial carbonated beverages tested in the study showed even higher concentrations, around 260 to 280 microplastic particles per liter.
Bubly is sold in aluminum cans rather than plastic bottles, which likely changes the exposure profile, but the inner lining of those cans is itself a polymer coating, and research on microplastic release specifically from can linings under carbonation pressure is still limited. The health effects of ingesting microplastics at these levels remain an open question in toxicology. Current evidence does not show clear harm at typical dietary exposure levels, but the field is young and evolving. If this concerns you, home carbonation using a glass carafe avoids both plastic bottles and can linings.
How Carbonation Actually Creates That Sensation
The fizzy, slightly biting sensation of sparkling water is not just about bubbles popping on your tongue. Research has shown that dissolved CO2 is converted by an enzyme on the tongue’s surface into carbonic acid, which then activates pain-sensing nerve fibers that project to the brain’s trigeminal system. When researchers blocked that enzyme with an inhibitor on one side of subjects’ tongues and then applied carbonated water to both sides, a significant majority rated the untreated side as having a stronger carbonation sensation.
This means the “taste” of carbonation is partly a mild pain signal, which is why some people find sparkling water refreshing and others find it unpleasant. It also explains why flat sparkling water tastes different from still water even though the bubbles are gone: residual carbonic acid still activates those receptors. That mild irritation is harmless for the vast majority of people, but it can aggravate conditions where the mouth or throat lining is already inflamed, such as canker sores or a sore throat.
Oral Bacteria and Sugar-Free Carbonation
One concern people sometimes raise is whether the acidity of sparkling water promotes bacterial growth in the mouth even without sugar. A randomized crossover trial in adolescents measured oral bacterial proliferation after consuming different carbonated drinks. Sugar-sweetened soda caused the largest bacterial increase, followed by artificially sweetened soda, and then carbonated water, which caused the smallest increase among the carbonated options. All three produced some measurable increase compared to baseline, but the gap between sugary soda and plain carbonated water was enormous.
The practical implication is that while carbonated water is not completely inert in the mouth the way still water is, it promotes far less bacterial activity than any sweetened drink. For oral health, what you are not putting in your mouth matters more than the mild acidity of what you are. The absence of sugar in Bubly is the dominant factor protecting your teeth from decay, even if the carbonation introduces a small amount of additional acidity.
Who Should Be Cautious
Most people can drink Bubly without any health concerns. But a few groups should pay attention:
- People with GERD or chronic heartburn: The temporary drop in lower esophageal sphincter pressure from carbonation can trigger reflux episodes. If you notice a pattern of heartburn after sparkling water, switching to still water with meals is a straightforward fix.
- People with irritable bowel syndrome: The gas from carbonation can worsen bloating and abdominal discomfort in people whose guts are already sensitive to distension.
- People with significant enamel erosion: If your dentist has already flagged thin enamel, adding more acidic beverages to your routine, even mildly acidic ones, works against you. This is especially relevant if you tend to sip throughout the day rather than drinking quickly.
- People managing kidney stones: Staying well hydrated is critical for kidney stone prevention, and sparkling water counts toward fluid intake. However, some flavored varieties from other brands add citric acid or sodium, which could matter depending on the type of stone. Bubly itself does not list added citric acid or sodium, but always check the label on any specific flavor.
For everyone else, including pregnant women, children, and older adults, unsweetened sparkling water like Bubly is considered safe by mainstream dietary guidelines. The carbonation is not pharmacologically active in any meaningful way. It is dissolved gas that your body burps or absorbs without issue.
The Natural Flavor Gray Area
One aspect of Bubly that does not get enough scrutiny is the “natural flavor” ingredient. This term covers a surprisingly wide range of compounds. The flavor formulations are proprietary, meaning PepsiCo does not disclose exactly which molecules create the lime or mango taste in each variety. For the vast majority of people this is a non-issue, since these compounds are used in trace amounts and are classified as safe by the FDA. But people with specific allergies or sensitivities occasionally react to natural flavor compounds, and the lack of transparency makes it hard to identify which product is the trigger. If you have unexplained symptoms that seem to track with flavored sparkling water, trying an unflavored version is a reasonable diagnostic step before assuming the carbonation is the problem.
There is also an ongoing consumer-advocacy push for greater disclosure of what “natural flavor” actually means on labels. Some competing brands have started listing specific flavor sources, such as “natural lime essence” or “grapefruit oil.” Bubly has not followed suit as of this writing. Whether this matters to you depends on how much you value ingredient transparency versus how much you simply enjoy the product and feel fine drinking it.