Sugary Gum Increases Nitrite and Lowers Blood Pressure After Vegetables

A recent study from King’s College London demonstrates that chewing sugary gum after consuming nitrate-rich vegetables such as beetroot, spinach, and kale can temporarily enhance the body's ability to lower blood pressure by increasing nitrite production.

Vegetables absorb nitrate from the soil, but this nitrate requires conversion by oral bacteria into nitrite before the body can utilize it. Nitrite functions to relax and dilate blood vessels, thereby improving circulation and reducing blood pressure. The conversion process depends on bacteria in the mouth, prompting researchers to explore methods to optimize it.

How Saliva Acidity Influences Nitrate Conversion

The research team investigated whether increasing saliva acidity could improve nitrate conversion. Since sugar-containing gum lowers mouth pH and makes saliva more acidic, the study tested if chewing such gum affects nitrite production and blood pressure response.

Dr. Andrew Webb, Clinical Senior Lecturer at King’s College London, explained: “Whether and how the acidity of the saliva in the mouth impacts the conversion of the inactive nitrate to the more active nitrite is a fundamental question, as it impacts a range of important physiological functions, including blood pressure. However, this process has not been studied much.”

He added that while previous research suggested increased acidity inhibits nitrate conversion, this had not been tested in the whole body over several hours. The team aimed to test if increasing saliva acidity would enhance nitrate-to-nitrite conversion.

Study Design and Findings on Gum and Blood Pressure

Healthy volunteers consumed a shot of beetroot juice and were randomly assigned to chew either sugar-containing gum (Hubba Bubba bubble gum) or sugar-free gum (Wrigley’s Extra) for three to six hours. Blood pressure was monitored, and blood and saliva samples were collected for analysis. After at least one week, participants repeated the experiment with the alternate gum.

Results showed that chewing sugar-containing gum lowered saliva pH by 1.4 units, making it more acidic compared to sugar-free gum. This was accompanied by a 45% increase in oral nitrite levels and a 25% increase in circulating nitrite in the body. Additionally, systolic and diastolic blood pressure decreased by nearly 3 and 2 mmHg respectively when chewing sugary gum versus sugar-free gum.

Implications and Cautions Regarding Sugary Gum

Despite the observed short-term blood pressure reduction, the researchers caution against using sugary gum as a therapeutic measure due to dental health concerns. Dr. Webb noted: “The effects were only short-term, lasting several hours, and long-term use of sugar-containing products would not be recommended for dental health.”

He also mentioned that traditional meals often end with a sweet dessert, which may temporarily enhance blood pressure-lowering effects when nitrate-rich vegetables are consumed earlier. Furthermore, sugary gum may have a greater impact than sugary drinks because it remains in the mouth longer.

Co-author Dr. Charlotte Mills from the University of Reading emphasized the role of oral bacteria in converting nitrate into compounds that relax blood vessels. She stated: “Our findings suggest that the presence of sugar may create a more favorable environment for this process.”

However, Dr. Mills stressed that frequent sugar consumption is harmful to dental and cardiometabolic health. The study serves as proof of concept that the body’s processing of dietary nitrate can be improved, and future research should focus on developing tooth-friendly methods that achieve similar effects.

Future Research Directions in Athletic Performance

Given that dietary nitrate is a recognized sports supplement, enhancing nitrate conversion could improve physiological benefits for athletes. The research team plans a larger study involving athletes to assess how sugary gum affects nitrate conversion, blood pressure, and performance.

The study referenced is titled “Lowering salivary pH with sugar-containing gum augments salivary nitrite production and blood pressure reduction with dietary nitrate (beetroot juice),” authored by Andrew J. Webb and colleagues, published on 18 June 2026 in the British Journal of Clinical Pharmacology. DOI: 10.1002/bcp.70640.