A new study of more than 2,000 older adults found that higher blood levels of vitamin C were associated with healthier brain structure and stronger neural connectivity.
Researchers linked vitamin C levels to the preservation of gray matter and the brain's default mode network, which plays a key role in memory and cognition.
Scientists caution that the study shows an association, not proof that vitamin C prevents cognitive decline or dementia.
There’s new evidence to suggest that diet plays a key role in how people age. The latest study recommends a diet with plenty of vitamin C.
Researchers in Japan have found that older adults with higher levels of vitamin C in their blood tended to have healthier brain structures and stronger connectivity in regions associated with memory and cognitive function. The findings, published in the journal PLOS One, add to growing evidence that nutrition may play an important role in brain health as people age.
The study analyzed data from 2,044 adults age 65 and older who participated in a community health project in Hirosaki City, Japan. Researchers measured vitamin C levels through blood samples and compared the results with MRI scans that assessed brain volume and neural connectivity.
Reduced gray matter volume
Participants with lower vitamin C levels were more likely to show reduced gray matter volume and weaker connectivity within the brain's default mode network, a collection of brain regions involved in memory, attention and self-reflection. Changes in this network have previously been linked to cognitive decline and neurodegenerative diseases such as Alzheimer's.
"Our study demonstrates that older adults with higher blood levels of vitamin C tend to have better-preserved brain structure and stronger connections within the default mode network," lead researcher Tomohiro Shintaku of Hirosaki University said in discussing the findings.
One of the study's notable features is its use of direct blood measurements rather than estimates of dietary intake. Previous research has linked diets rich in vitamin C to better cognitive outcomes, but few studies have examined how actual blood concentrations relate to brain structure.
Researchers adjusted for a variety of factors that can influence brain health, including age, education, physical activity and chronic health conditions. Even after accounting for those variables, the relationship between vitamin C levels and brain health remained significant.
Don’t jump to conclusions
However, experts urge caution in interpreting the results.
Because the research was observational and measured vitamin C levels at only one point in time, it cannot establish a cause-and-effect relationship. It's possible that other factors, including overall diet quality, body weight or socioeconomic conditions, contributed to the observed differences.
“Our study demonstrates that older adults with higher blood levels of vitamin C tend to have better-preserved brain structure (gray matter) and stronger connections within the default mode network (DMN), a crucial brain network involved in memory and cognitive function,” Tomohiro Shintaku, MD, PhD, assistant professor in the Department of Radiology Graduate School of Medicine at Hirosaki University, told Fox News Digital.
Vitamin C is a powerful antioxidant that helps protect cells from damage caused by oxidative stress, a process believed to contribute to aging and neurodegenerative disease. The vitamin is abundant in fruits and vegetables, including oranges, strawberries, kiwi, broccoli and bell peppers.
The researchers say future studies will be needed to determine whether maintaining higher vitamin C levels can directly slow brain aging or reduce the risk of dementia. For now, the findings offer another reason to maintain a diet rich in fruits and vegetables as part of a broader strategy for healthy aging.