Plain sparkling water, the kind with no added sugar or sweeteners, does not raise blood sugar and is a perfectly reasonable drink for people managing diabetes. Research shows that carbonation itself has no measurable effect on your glycemic response, so the bubbles are not a problem. Where things get more interesting is in the details: which type of sparkling water you choose, whether it contains artificial sweeteners or citrus flavoring, and whether it helps you cut back on drinks that genuinely do cause blood sugar trouble.
Carbonation Alone Does Not Raise Blood Sugar
One of the most common worries is that the carbon dioxide dissolved in sparkling water somehow changes how your body processes sugar. It doesn’t. A controlled study tested drinks at different carbonation levels and measured both gastric emptying and blood sugar. Higher carbonation temporarily expanded the stomach area in the first 20 minutes after drinking, which makes sense since fizzy liquid takes up more space. But that expansion had no effect on how quickly the stomach emptied, how full people felt, or their glycemic response.1PubMed. No influence of carbonation on glycemic response, gastric emptying, and satiety of sweetened drinks The bubbles are cosmetic as far as your blood sugar is concerned.
This is worth emphasizing because it separates sparkling water from the drinks people often confuse it with. Soda, tonic water, and many commercial “sparkling” beverages contain sugar. The carbonation in those drinks isn’t the issue; the sugar is. Strip out the sugar, and you’re left with water that happens to tingle on your tongue.
Why Replacing Sugary Drinks with Sparkling Water Helps
The clearest benefit of sparkling water for diabetes management isn’t anything the bubbles do. It’s what they replace. If you’re someone who regularly drinks regular soda, sweet tea, or fruit juice, switching to unsweetened sparkling water removes a significant source of rapidly absorbed sugar from your diet. A single can of regular soda can contain around 40 grams of sugar, nearly the entire daily added-sugar limit recommended by most health authorities. Multiply that by two or three cans a day, and you’re looking at a constant stream of glucose that your body has to manage.
Large observational studies consistently show that swapping one daily sugary drink for water, coffee, or tea is associated with a lower risk of developing type 2 diabetes and better long-term blood sugar control. Sparkling water fits neatly into that substitution because it addresses one of the main reasons people drink soda in the first place: they want something more interesting than flat water. The fizz, the cold bite, the sensation of drinking something with texture all help satisfy that craving without the metabolic cost.
Flavored and Sweetened Sparkling Water
Not every sparkling water is plain. The market has exploded with flavored varieties, and the sweetener they use matters a lot for diabetes management. Broadly, flavored sparkling water falls into three categories: unsweetened (flavored only with natural essences), artificially sweetened, and sugar-sweetened. The first category is generally fine from a blood sugar standpoint. The third is essentially soda in a fancier bottle. The middle category deserves a closer look.
On the immediate blood sugar question, artificially sweetened sparkling water appears safe. Studies comparing regular sugar-sweetened cola to diet versions found that both blood glucose and insulin stayed stable after drinking the diet versions, while regular cola caused a sharp spike in both.2Integrative Food, Nutrition and Metabolism. Blood glucose and insulin response to artificially- and sugar-sweetened sodas in healthy men A separate trial comparing nutritive and non-nutritive sweetened sodas reached the same conclusion: blood glucose and insulin rose only after the sugar-sweetened version, with no acute effects from the artificially sweetened one.3The FASEB Journal. Acute Response of Nutritive vs Non‐Nutritive Sweeteners in Sodas on Blood Glucose, Insulin and Levels of Satiety
The longer-term picture is less tidy. A growing body of research links regular consumption of artificial sweeteners to changes in gut bacteria. Multiple sweeteners, including sucralose, aspartame, saccharin, and acesulfame-K, have been associated with reducing beneficial bacterial populations and encouraging less helpful ones.4PubMed Central. Exploring the Long-Term Effect of Artificial Sweeteners on Metabolic Health Those microbial shifts have been tied to impaired glucose metabolism and heightened inflammation, both of which work against diabetes management.5PubMed. Artificial Sweeteners and Gut Microbiota: Mechanistic Insights and Implications for Metabolic Health The research is still evolving and much of it comes from animal models or short-term human studies, so it would be premature to say artificial sweeteners are harmful for everyone. But if you’re choosing between plain sparkling water and artificially sweetened sparkling water, the plain version carries no gut-related uncertainty at all.
Bicarbonate-Rich Mineral Water
Some naturally sparkling mineral waters are rich in bicarbonate, and this is where the research gets genuinely intriguing for people with diabetes. A study examining bicarbonate mineral water consumption found that a marker of blood sugar control called glycoalbumin dropped during periods when participants drank the mineral water compared to when they drank regular tap water. Fasting glucose showed a trend toward improvement as well, though it didn’t reach the threshold for statistical significance.6PubMed Central. The Consumption of Bicarbonate-Rich Mineral Water Improves Glycemic Control The researchers suggested that bicarbonate mineral water may help prevent or improve type 2 diabetes without changing how much insulin the body produces or how resistant to insulin it is.
A separate study in postmenopausal women found that insulin concentrations followed a different pattern after drinking bicarbonate-rich mineral water compared to low-mineral water. At two hours after a meal, insulin levels were lower in the mineral water group, suggesting the body needed less insulin to handle the same glucose load. The effect was most pronounced in women who already had higher insulin resistance.7PubMed. Does bicarbonated mineral water rich in sodium change insulin sensitivity of postmenopausal women? A recent review proposes that the alkalizing effect of bicarbonate water may enhance insulin receptor binding, which would explain the improved glycemic control.8PubMed Central. Beyond Thirst: Influence of Bicarbonate Mineral Water on Cardiovascular Risk Factors, Gastrointestinal Function, and Liver Health
These are small studies and early-stage findings, not the kind of evidence that should drive major dietary changes on their own. But they do suggest that if you’re already drinking sparkling water, choosing a naturally bicarbonate-rich mineral water over a generic carbonated water could offer a modest edge. Brands vary widely in their mineral content, so checking the label for bicarbonate levels is worthwhile if this interests you.
Effects on Snacking and Weight
For people with type 2 diabetes, weight management and snacking habits are often just as important as what’s in your glass. A randomized trial in healthy Japanese adults compared a group drinking carbonated water to a group drinking still water over 12 weeks. The carbonated water group reduced their snacking frequency by about 1.4 fewer times per week at the four-week mark, and that reduction held steady at 12 weeks. The same group also cut their alcohol intake and lost a modest but statistically significant amount of weight, roughly three-quarters of a kilogram more than the still-water group.9Nature / Scientific Reports. Randomized trial of carbonated water consumption on snacking behavior, alcohol intake, and health indices in healthy Japanese adults
These are not dramatic changes, and the study was conducted in people without diabetes. But for someone trying to manage blood sugar, snacking less often and losing even a small amount of weight can improve insulin sensitivity. The mechanism likely has more to do with the sensation of fullness that carbonation provides than with any metabolic effect of the gas itself.
One study complicates this picture slightly. Research in rats found that drinking carbonated beverages increased levels of ghrelin, a hormone that stimulates hunger, and led to greater food intake compared to still beverages. A small parallel study in 20 human males also found elevated ghrelin levels after carbonated drinks.10PubMed. Carbon dioxide in carbonated beverages induces ghrelin release and increased food consumption in male rats: Implications on the onset of obesity The rat findings were more dramatic than the human ones, and the randomized trial described above found the opposite behavioral outcome in practice, with carbonated water drinkers actually snacking less. The ghrelin finding hasn’t been replicated widely in humans, and real-world behavior seems to favor the fizzy water. Still, if you notice that sparkling water makes you hungrier, you’re not imagining things; there may be a hormonal basis for it in some people.
Dental Erosion from Flavored Varieties
People with diabetes already face a higher risk of dental problems, so it’s worth knowing that flavored sparkling waters can erode tooth enamel over time. A study testing several flavored sparkling waters found that all of them had pH values below the critical threshold for enamel dissolution. Enamel specimens showed measurable mass loss after just one day of immersion, and the erosion accumulated with continued exposure.11Brazilian Dental Science. The long-term effect of sparkling flavored water on human tooth enamel determined by gravimetric analysis: a preliminary evaluation The citric acid added for flavor, not the carbonation, is the primary culprit. Plain sparkling water without added flavoring has a pH that is only slightly lower than still water and is far less erosive.
The practical implication: if you’re drinking flavored sparkling water throughout the day, you’re bathing your teeth in mild acid repeatedly. Drinking it with meals rather than sipping constantly, or switching to unflavored varieties, limits the exposure. This isn’t unique to sparkling water; any acidic beverage does the same thing. But since people with diabetes often increase their water intake and may reach for flavored sparkling water as a more enjoyable option, the cumulative effect is worth knowing about.
Bone Health, Kidney Function, and Blood Pressure
Three common concerns about carbonated water, that it weakens bones, harms kidneys, or raises blood pressure, have been studied and largely put to rest for people drinking plain or non-cola sparkling water.
On bones: a study of older women found that bone mineral density was not associated with intake of any type of carbonated beverage after accounting for age, weight, calcium intake, exercise, and medication use.12PubMed Central. Carbonated beverage consumption and bone mineral density among older women: the Rancho Bernardo Study The bone-weakening reputation of carbonated drinks comes primarily from cola, which contains phosphoric acid. Plain sparkling water contains carbonic acid, which is far weaker and does not have the same association.13The American Journal of Clinical Nutrition. Colas, but not other carbonated beverages, are associated with low bone mineral density in older women: The Framingham Osteoporosis Study
On kidneys: people with diabetes are often monitoring kidney health closely, since diabetes is a leading cause of chronic kidney disease. An epidemiological analysis found that non-cola carbonated beverages had no association with chronic kidney disease.14PubMed Central. Carbonated Beverages and Chronic Kidney Disease Cola-type drinks were the ones linked to kidney problems, likely due to their phosphoric acid content rather than carbonation.
On blood pressure: some naturally sparkling mineral waters contain sodium, which raises obvious concerns for people managing both diabetes and cardiovascular risk. A study specifically testing sodium-rich carbonated mineral water found no differences in blood pressure compared to low-sodium water, either during the trial or relative to baseline.15PubMed. Sodium-rich carbonated natural mineral water ingestion and blood pressure That said, sodium recommendations for people with diabetes-related hypertension are strict, and if your doctor has put you on a low-sodium diet, you should still check the label rather than assuming all sparkling water is sodium-free. Some mineral waters contain meaningful amounts.
What Your Sparkling Water Comes In
A dimension of sparkling water that rarely comes up in diabetes conversations is the packaging. A study examining non-alcoholic beverages across different packaging types found endocrine-disrupting chemicals in the vast majority of products tested. These chemicals, including PFAS, bisphenols, and parabens, were detected in nearly 90 percent of the screened beverages. Concentrations were highest in drinks packaged in metal cans and lowest in glass and carton containers.16PubMed. Exposure to endocrine disrupting chemicals from beverage packaging materials and risk assessment for consumers
Endocrine disruptors are chemicals that can interfere with hormone signaling, and some research links certain ones to insulin resistance and metabolic dysfunction. For someone already dealing with a metabolic condition like diabetes, minimizing unnecessary exposure to these compounds is a reasonable precaution. If you’re drinking several sparkling waters a day, choosing glass bottles over cans when practical could reduce your exposure. This isn’t a reason to avoid sparkling water; it applies equally to any canned beverage. But since people often increase their sparkling water intake when using it as a soda replacement, the cumulative exposure from packaging becomes more relevant.
Home carbonation systems, which let you carbonate tap or filtered water yourself in a glass bottle, sidestep the packaging issue entirely. They also eliminate any uncertainty about added sweeteners or flavoring agents, since you control exactly what goes into the water. For someone drinking multiple servings of sparkling water daily as part of a diabetes management strategy, making it at home is the cleanest option from both a metabolic and a chemical-exposure standpoint.