A preprint study posted in July 2025 found that esports players who drank sparkling water during gaming sessions committed fewer in-game errors and reported less cognitive fatigue than those drinking plain water. The finding sits at the intersection of two fast-growing fields: competitive gaming and hydration neuroscience. If the results hold up under peer review, they could reshape how players think about what they drink during long sessions, and whether the fizz itself is doing real work inside the brain.
Fewer Errors, Less Fatigue: The Esports Trial
The central piece of evidence comes from a study posted on bioRxiv that measured how sparkling water affected cognitive performance during extended esports play. Researchers tracked blood glucose and salivary cortisol at regular intervals while players competed, and found that sparkling water significantly attenuated markers of cognitive fatigue compared to plain water. The same trial recorded that players committed fewer in-game errors when drinking carbonated water, a result the authors said supported their hypothesis that the sensory properties of carbonation could sustain attention over time.
Separately, the same research team highlighted that pupil constriction, which scientists use as a physiological marker of cognitive fatigue, was less pronounced in the sparkling water group. The study also reported that sparkling water boosted enjoyment during esports sessions. That last detail matters because subjective enjoyment is linked to sustained voluntary effort. A player who feels better about the experience is more likely to maintain focus across a multi-hour session. Still, this is a preprint, not yet peer-reviewed, and the sample size has not been disclosed in the available highlights. Readers should treat these results as promising but preliminary.
Why Carbonation May Boost Cerebral Blood Flow
The esports findings did not emerge from nowhere. A 2022 crossover experiment involving 17 young adults compared cold carbonated water against noncarbonated water under ambient heat stress. That trial, published in Physiology and Behavior, found that carbonated water produced higher middle cerebral artery mean blood velocity, a standard index of cerebral blood flow. Participants also reported reduced sleepiness and increased motivation after drinking the carbonated version. Both drinks raised mean arterial pressure, but the carbonated water showed a stronger effect on the brain’s blood supply specifically.
The mechanism likely involves trigeminal nerve stimulation. Dissolved carbon dioxide activates receptors in the mouth and throat that send signals to the brainstem, triggering a mild arousal response. That sensory jolt may explain why carbonated water seems to fight drowsiness more effectively than still water, even when both deliver identical hydration. For gamers sitting in warm rooms with multiple monitors generating heat, this effect could be especially relevant. The 2022 study was small, though, and conducted under controlled heat stress rather than during actual gaming, so direct extrapolation to esports requires caution.
Hydration and Cognition: The Broader Evidence Base
Strip away the carbonation question and the underlying science on hydration and brain performance is well established. A peer-reviewed review published in the British Journal of Nutrition synthesized experimental evidence showing that even mild dehydration dulls alertness and disrupts mood. The review found that water intake improved both alertness and calmness, and it mapped out earlier primary trials connecting thirst states to measurable drops in cognitive output. The takeaway is straightforward: any drink that keeps a gamer hydrated will support baseline brain function, and sparkling water may add a sensory bonus on top of that.
Population-level data tells a similar story. An epidemiologic analysis of approximately 2,506 adults aged 60 or older, drawn from NHANES 2011 through 2014, linked calculated serum osmolarity and water intake to performance on the Digit Symbol Substitution Test, which measures attention and processing speed. The study reported moderate associations between better hydration and sharper cognitive scores. While these participants were older adults rather than young gamers, the direction of the relationship is consistent: dehydration taxes the brain, and adequate fluid intake protects it. The NHANES dataset, maintained by the CDC’s National Center for Health Statistics, provides the codebooks and lab methods that allow independent verification of how osmolarity was computed, underscoring that the observed relationship between hydration and cognition is grounded in systematically collected data rather than anecdote.
The Enamel Problem With Flavored Varieties
Before gamers stock their mini-fridges with cases of flavored sparkling water, dental research raises a clear caution. A study published in the Journal of Oral Rehabilitation assessed the pH, titratable acidity, and in-vitro erosive effects of flavored sparkling waters on both hydroxyapatite discs and extracted human teeth. Several flavored varieties had low pH levels and measurable erosive potential, meaning they could soften and wear down enamel with repeated exposure. Related work on acidic beverages and dental erosion supports the same concern, showing that drinks with high acidity and certain flavoring profiles can cause cumulative surface loss over time.
This tradeoff is worth thinking through for anyone considering sparkling water as a performance aid. Unflavored varieties that use only dissolved carbon dioxide in water tend to be less erosive than those containing added acids or citrus flavorings, but they still lower pH compared with plain water. For players who sip slowly over many hours, that extended contact time with enamel could magnify risk. Practical strategies such as drinking with meals, avoiding constant sipping between matches, and rinsing with plain water after finishing a can may help reduce exposure. For now, the emerging picture is nuanced: carbonation may support alertness and enjoyment during esports through both physiological and sensory pathways, but relying heavily on acidic flavored products introduces a separate dental cost that competitive gamers, and the brands that market to them, will have to weigh carefully.
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*This article was researched with the help of AI, with human editors creating the final content.
