By Sulphine Bonabana
Drinking beet juice every day for two weeks may help lower blood pressure in older adults, according to new research linking the drink’s nitrate content to changes in bacteria found in the mouth.
The study found that concentrated nitrate-rich beet juice lowered blood pressure among older adults, but did not produce the same effect in younger adults.
Researchers say the finding could help explain why nitrate-rich foods such as beets and leafy vegetables are often associated with better heart health.
Beets are naturally rich in nitrates. When eaten or drunk, nitrates are converted by bacteria in the mouth into nitrites, which the body then turns into nitric oxide. Nitric oxide helps relax and widen blood vessels, improving blood flow and reducing blood pressure.
The study involved 36 older adults aged 67 to 79 and 39 younger adults aged 18 to 30. Both groups took part in trial periods where they drank concentrated nitrate-rich beet juice twice a day for two weeks. They also went through another period where they drank a nitrate-free placebo.
Researchers measured their blood pressure and studied changes in their oral microbiome, the community of bacteria that live in the mouth, before and after each trial period.
The results showed that beet juice changed the oral microbiome in both younger and older adults, but the effect was more pronounced among older participants.
Among the older adults, researchers found lower levels of Prevotella, a type of mouth bacteria linked to poorer oral health, and higher levels of Neisseria, considered a more beneficial bacteria. The same group also recorded a drop in blood pressure.
“This study shows that nitrate-rich foods alter the oral microbiome in a way that could result in less inflammation, as well as a lowering of blood pressure in older people,” said Andrew Jones, PhD, a co-author of the study and professor of applied physiology at the University of Exeter.
The findings add to growing research linking mouth bacteria, diet and heart health.
Anni Vanhatalo, PhD, the study’s lead author, said nitrate-rich foods may be especially useful as people age because older adults produce less nitric oxide naturally.
“We know that a nitrate-rich diet has health benefits, and older people produce less of their own nitric oxide as they age,” she said.
Vanhatalo said older adults are also more likely to have high blood pressure, which increases the risk of heart attack and stroke.
“Encouraging older adults to consume more nitrate-rich vegetables could have significant long-term health benefits,” she said.
Researchers also noted that beet juice is not the only source of dietary nitrates. People who do not like beetroot can get nitrates from vegetables such as spinach, arugula, fennel, celery and kale.
Lee Beniston, associate director for Industry Partnerships and Collaboration at the Biotechnology and Biological Sciences Research Council in the United Kingdom, which funded the study, said the research shows the role nutrition can play in healthy ageing.
“This research is a great example of how bioscience can help us better understand the complex links between diet, the microbiome, and healthy aging,” he said.
The study does not suggest that beet juice should replace prescribed blood pressure medicine. People already being treated for hypertension should speak to a health worker before making major changes to their diet.
