Medical Bulletin 27/May/2026

Here are the top medical news for today:

Beet Juice May Lower Blood Pressure in Older Adults Within Two Weeks: Study

Your mouth may be doing far more for your heart than you realize. Scientists have discovered that the bacteria living on your tongue and gums could influence how well your body controls blood pressure — and beetroot juice appears to help.

A new study from the University of Exeter found that older adults who drank nitrate-rich beetroot juice twice daily for two weeks experienced a noticeable drop in blood pressure. Surprisingly, the benefit seemed to come not just from the beetroot itself, but from the way it changed the balance of bacteria in the mouth.

Researchers say certain oral bacteria help convert dietary nitrate into nitric oxide, a molecule that relaxes blood vessels and improves circulation. Nitric oxide production naturally declines with age, which may partly explain why blood pressure often rises in older adults.

The study included adults under 30 and adults in their 60s and 70s. Participants drank either nitrate-rich beetroot juice or a placebo version with the nitrate removed. Scientists then analyzed changes in the oral microbiome — the community of bacteria living in the mouth.

In older adults, beetroot juice increased levels of beneficial bacteria while reducing potentially harmful bacteria. At the same time, blood pressure dropped significantly. Younger adults also showed microbiome changes, but they did not experience the same blood pressure benefit.

Researchers believe the findings highlight how closely nutrition, oral health, and cardiovascular function are connected. The mouth acts as the first step in a chain reaction that allows nitrate-rich foods to support nitric oxide production throughout the body.

Beetroot is one of the richest dietary sources of nitrate, but other vegetables like spinach, arugula, kale, celery, and fennel also contain high amounts.

Scientists caution that beetroot juice is not a replacement for blood pressure medication. The studies are still relatively small, and more research is needed to understand why some people respond more strongly than others.

Still, the research points to a fascinating possibility: healthier blood vessels may begin with healthier mouth bacteria.

RESEARCH: Anni Vanhatalo, Joanna E. L\'Heureux, Matthew I. Black, Jamie R. Blackwell, Kuni Aizawa, Christopher Thompson, David W. Williams, Mark van der Giezen, Paul G. Winyard, Andrew M. Jones. Ageing modifies the oral microbiome, nitric oxide bioavailability and vascular responses to dietary nitrate supplementation. Free Radical Biology and Medicine, 2025; 238: 682 DOI: 10.1016/j.freeradbiomed.2025.07.002

AI Body Mapping Reveals Hidden Obesity-Linked Damage to Facial Nerves, Study Finds

Obesity may be damaging the body in ways scientists never realized — right down to the nerves in the face. Using a powerful new artificial intelligence system, researchers have mapped disease-related changes across an entire mouse body and uncovered previously hidden nerve damage linked to obesity.

The breakthrough study, published in Nature, was led by scientists at Helmholtz Munich and Ludwig Maximilians University Munich. Their new AI platform, called MouseMapper, can analyze whole-body scans at cellular-level detail, allowing researchers to study how diseases affect multiple organs and tissues simultaneously.

To create these detailed maps, scientists made mice transparent using special tissue-clearing techniques while preserving fluorescent markers attached to nerves and immune cells. Advanced light-sheet microscopes then captured three-dimensional images of the entire body, producing enormous datasets containing millions of cellular structures.

MouseMapper analyzed the scans automatically, identifying 31 different organs and tissue types while tracking nerve networks and inflammation throughout the body.

When researchers used the system to study obesity, they discovered widespread immune changes and unexpected nerve damage. One of the most surprising findings involved the trigeminal nerve, a major facial nerve responsible for sensation and some motor functions.

In obese mice, these facial nerves had fewer branches and damaged nerve endings, suggesting impaired nerve function. Behavioral tests supported the discovery, showing that obese mice were less sensitive to touch and sensory stimulation compared with lean mice.

Scientists also found inflammation-related molecular changes inside the trigeminal ganglion, the cluster of nerve cells connected to facial sensation. Importantly, many of the same molecular patterns were later identified in human tissue from people with obesity, suggesting similar nerve damage could occur in humans as well.

The team believes MouseMapper could become a major tool for studying complex diseases such as diabetes, cancer, and neurodegenerative disorders. By creating detailed “digital twins” of organisms, scientists hope future AI systems may help detect diseases earlier, test treatments virtually, and reduce the need for animal experiments.

REFERENCE: Doris Kaltenecker, Izabela Horvath, et al.; A deep-learning framework reveals whole-body perturbations at cell level. Nature, 2026; DOI: 10.1038/s41586-026-10535-2