Chewing Sugar Gum Boosts Beetroot Juice’s Blood Pressure Benefits by 25%

Chewing a stick of Hubba Bubba while drinking beetroot juice sounds like an odd health tip, but a small crossover study published in June 2026 suggests the combination is more than a coincidence. Researchers found that the acidity of sugar-containing gum drops salivary pH enough to rev up the bacteria in your mouth that convert dietary nitrate into nitrite, the intermediate compound that ultimately relaxes blood vessels. The effect was measurable in blood plasma and in blood pressure readings, though the sample was small and the participants were all healthy volunteers.

How Beetroot Juice Lowers Blood Pressure Through Oral Bacteria

The pathway starts in your saliva. When you eat nitrate-rich foods like beetroot, the nitrate is concentrated in salivary glands and secreted into the mouth, where oral bacteria reduce nitrate to nitrite in what researchers call the enterosalivary circulation. That nitrite is swallowed, absorbed, and converted further into nitric oxide (NO) in the bloodstream, where it acts as a potent vasodilator. Dietary nitrate from vegetables has attracted growing interest as a contributor to cardiovascular health precisely because of this chain reaction. Disrupting it, say by spitting out saliva or rinsing with antibacterial mouthwash, blunts both plasma nitrite rises and blood pressure reductions.

The new study, led by Webb AJ and colleagues, asked a simple question: if oral bacteria drive the conversion, and bacterial enzyme activity is sensitive to pH, could deliberately acidifying the mouth make the process more efficient?

Sugar Gum Dropped Salivary pH and Raised Nitrite by 45%

14 healthy volunteers completed a seven-hour crossover trial, attending two separate sessions. On each visit they drank 70 mL of beetroot juice containing 400 mg of nitrate, then chewed either acidic sugar-containing gum (Hubba Bubba, pH 2.84) or sugar-free gum (Extra, pH 6.71) throughout most of the session. Salivary pH, saliva volume, salivary and plasma nitrate and nitrite, and blood pressure were tracked at regular intervals for up to six hours.

The sugar-containing gum reduced salivary pH by 1.4 units compared to the sugar-free control, a highly significant difference. That shift in acidity translated directly into a 45% increase in salivary nitrite production, amounting to an additional 30.0 micromoles per hour. Plasma nitrite, the downstream marker of how much nitrite actually entered the bloodstream, rose by 25%, an increase of 222.2 nanomoles per litre. The salivary nitrate-to-nitrite ratio fell, confirming that more nitrate was being converted rather than simply passing through. Saliva volume also increased with the sugar gum, which the authors note may contribute by delivering more nitrate to bacterial surfaces. A meta-analysis of randomized controlled trials has previously linked inorganic nitrate consumption to reductions in systolic blood pressure, providing context for why amplifying this conversion step could matter clinically.

Blood Pressure Fell by 2.7 mmHg Systolic With Sugar Gum

The blood pressure changes were modest but statistically robust. Systolic blood pressure fell by an additional 2.7 mmHg with the sugar-containing gum compared to sugar-free gum (p < .0001), and diastolic pressure fell by 1.9 mmHg (p < .0001). These numbers matter in a population context: even small sustained reductions in systolic pressure are associated with meaningful reductions in stroke and heart attack risk at a population level. The effect appeared from about one hour after beetroot juice ingestion and wore off by the sixth hour, suggesting the mechanism is acute rather than lasting.

Critically, there was no significant change in salivary or plasma nitrate levels between the two conditions, which means the gum was not altering how much nitrate was secreted or absorbed. The bacteria were simply doing more with what was there.

Study Design Strengths and Key Caveats

The crossover design, where each participant served as their own control on two separate visits, is a methodological strength that limits confounding from individual differences in oral microbiome composition. Participants fasted for 12 hours before each session, avoided high-nitrate foods, strenuous exercise, smoking, and mouthwash for 24 hours beforehand, and blood pressure was measured in triplicate every 15 minutes for the first three hours. That level of protocol rigour is notable for a study of this size.

The limitations deserve equal attention. The final sample of 14 was not pre-specified; it was expanded from an initial 8 after an interim review, which the authors acknowledge carries statistical caveats. All participants were healthy volunteers, so extrapolating to people with hypertension requires caution. Salivary nitrate data from the second cohort of six volunteers were contaminated and excluded. Both gums contained multiple additives including acesulfame-K and aspartame, so ingredients beyond sugar and acidity could theoretically have independent effects, though the two gum formulations were otherwise similar. Factors that impair the enterosalivary pathway, such as antiseptic mouthwash and proton pump inhibitors, are well-documented, but the reverse, deliberate enhancement of bacterial activity through pH manipulation, is less studied. Whether chronic acidification of the mouth would eventually alter the composition of the oral microbiome in ways that could backfire is an open question the study was not designed to answer.

What This Means for Diet and Future Research

The findings carry a small but genuine irony: the classic sequence of a sugary dessert after a nitrate-rich meal, culturally ubiquitous and nutritionally frowned upon, may actually boost salivary nitrate reduction. The authors flag this pattern but are careful to note that excess sugar carries its own risks, including hyperglycemia, which can blunt beetroot juice's blood-pressure effects. The point is mechanistic, not a licence to eat candy after every salad.

For researchers, the study opens a practical handle on the nitrate pathway. If salivary pH is a tunable variable, other acidic but less calorically problematic agents could potentially serve the same function. There is already interest in oral nitrate-reducing bacteria as future probiotic targets for blood pressure management, and understanding which environmental conditions optimise their activity is a necessary step in that direction. Whether acidifying the mouth before or during nitrate intake could meaningfully enhance exercise performance, another proposed benefit of the nitrate pathway, is also worth testing in future trials with pre-registered sample sizes and hypertensive populations.

Evidence rating

EMERGING — 82/100

Caveats:

• Very small sample: only 14 healthy volunteers — results may not apply to people with hypertension or other conditions.
• Sample size was not set in advance; it was expanded mid-study based on interim results, which can inflate effect estimates.
• The blood pressure reduction wore off by hour six, suggesting the effect is transient and acute only.
• Excess sugar carries real health risks including hyperglycemia, which can itself blunt nitrate's blood pressure-lowering effect — the authors explicitly caution against routine high-sugar use.
• Funding source was not disclosed by the authors.

Randomized crossover trial in 14 healthy adults. Demonstrates a mechanistic chain from salivary pH reduction to increased bacterial nitrate-to-nitrite conversion, elevated plasma nitrite, and modest blood pressure lowering — association is causal by design, though the small sample and mid-study expansion of the cohort limit confidence in the effect sizes. Findings are consistent with prior enterosalivary circulation research but have not yet been independently replicated at scale.

References

1. Andrew J. Webb, Harriet Clift, Callum Hill, et al. (2026). Lowering salivary pH with sugar‐containing gum augments salivary nitrite production and blood pressure reduction with dietary nitrate (beetroot juice). British Journal of Clinical Pharmacology. https://doi.org/10.1002/bcp.70640
2. Vikas Kapil, Syed M.A. Haydar, Vanessa Pearl, Jon O. Lundberg, Eddie Weitzberg, Amrita Ahluwalia (2013). Physiological role for nitrate-reducing oral bacteria in blood pressure control. Free Radical Biology and Medicine. https://doi.org/10.1016/j.freeradbiomed.2012.11.013
3. Catherine P. Bondonno, Kevin D. Croft, Jonathan M. Hodgson (2016). Dietary Nitrate, Nitric Oxide, and Cardiovascular Health. Critical Reviews in Food Science and Nutrition. https://doi.org/10.1080/10408398.2013.811212
4. Inorganic nitrate consumption and blood pressure in randomized controlled trials: a systematic review and meta-analysis – PMC. NIH. https://pmc.ncbi.nlm.nih.gov/articles/PMC10052955/
5. Abrar M. Babateen, Oliver M. Shannon, John C. Mathers, Mario Siervo (2019). Validity and reliability of test strips for the measurement of salivary nitrite concentration with and without the use of mouthwash in healthy adults. Nitric Oxide. https://doi.org/10.1016/j.niox.2019.07.002
6. Xiaofen Chai, Libing Liu, Feng Chen (2024). Oral nitrate-reducing bacteria as potential probiotics for blood pressure homeostasis. Frontiers in Cardiovascular Medicine. https://doi.org/10.3389/fcvm.2024.1337281