Low Vitamin C Levels Linked to Reduced Brain Connectivity, Study Finds - Video

A simple nutrient found in oranges, strawberries, and other fruits may play a bigger role in brain health than previously thought, according to a new study involving more than 2,000 older adults.

Researchers from Hirosaki University in Japan analyzed brain scans and blood samples from 2,044 adults aged 64 and older to investigate whether vitamin C levels were linked to brain structure and connectivity. Their findings, published in PLOS One, suggest that lower vitamin C levels in the blood are associated with changes in key areas of the brain involved in memory and thinking.

Using MRI scans, the researchers measured participants' gray matter volume and examined connectivity within the brain's default mode network, a group of interconnected brain regions that supports functions such as attention, memory, and self-reflection.

Researchers found that participants with lower blood vitamin C levels tended to have less gray matter and weaker connectivity within the default mode network compared with those who had higher vitamin C levels.

Gray matter contains most of the brain's nerve cells and plays an important role in processing information. Reduced gray matter volume and weaker network connectivity have previously been linked to age-related cognitive decline and dementia risk.

Researchers caution that the study does not prove that vitamin C directly protects the brain.

Still, the results suggest that maintaining adequate vitamin C levels through a balanced diet may support healthy brain aging. Scientists say further studies are needed to determine whether improving vitamin C status can help preserve cognitive function and reduce age-related decline.

REFERENCE: Nagaya, H., et al. (2026) Plasma vitamin C levels are associated with brain structural networks on MRI: A large cohort study. PLoS One. DOI: 10.1371/journal.pone.0348504. https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0348504