Chewing Gum After a Beetroot Drink Nudged Blood Pressure Down, a Surprising New Study Finds

In one of the more unusual nutrition experiments of the year, researchers found that chewing gum after drinking beetroot juice temporarily lowered volunteers' blood pressure, offering a new clue about how the vegetables we eat interact with the bacteria in our mouths.

The finding builds on well-established science. Nitrate, a compound abundant in beetroot and leafy greens such as spinach and kale, is converted by bacteria living in the mouth into nitrite. Nitrite in turn helps relax and widen blood vessels, which lowers blood pressure. Scientists at King's College London, working with colleagues at the University of Reading, wanted to know whether changing the acidity of saliva could make that conversion more efficient.

To test the idea, healthy volunteers drank beetroot juice and then chewed gum for three to six hours. In some sessions they chewed sugar-containing gum, in others a sugar-free brand. Throughout, the researchers collected blood and saliva samples and monitored the participants' blood pressure to track what was happening inside their bodies.

The results centered on the sugary gum, which made the mouth more acidic. Saliva acidity increased by about 1.4 pH points, and that shift appeared to supercharge the nitrate-to-nitrite pathway. Nitrite levels in the mouth rose by 45%, and the amount of nitrite circulating in the blood climbed by 25%. Correspondingly, systolic blood pressure, the top number in a reading, fell by roughly 3 millimeters of mercury, and diastolic pressure dropped by about 2.

"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," said lead researcher Dr. Andrew Webb, describing the work, which was published in the British Journal of Clinical Pharmacology. Understanding that mechanism, he suggested, could help explain why the same nitrate-rich diet affects different people differently.

The scientists were careful to temper any enthusiasm. The blood-pressure effect was modest and temporary, lasting only a few hours, and it emerged specifically with sugary gum, which carries well-known risks for dental and metabolic health. The researchers explicitly cautioned against anyone treating gum as a strategy for managing high blood pressure. Instead, they framed the study as a window into the surprisingly intricate chemistry linking diet, the mouth's microbes and the cardiovascular system, a relationship that may one day inform smarter, safer ways to help people keep their blood pressure in check.