A diet rich in vitamin C doesn’t just boost the immune system, it may also help keep the brain healthy in old age.
That’s according to a Japanese study of more than 2,000 older adults that found those with lower levels of vitamin C in their blood plasma had a lower volume of gray matter in their brains.
Because gray matter is responsible for processing information and controlling movement, low levels can lead to cognitive decline and memory issues.
Previous research has uncovered associations between diets higher in vitamin C, found in oranges and bell peppers, and lower risk of cognitive impairment in older adults.
But few studies have looked directly at vitamin C levels in blood plasma and potential associations with brain structure and connectivity within brain networks.
“Our study demonstrates that higher plasma vitamin C levels are associated with better preserved structural connectivity of the default mode network (DMN), a key brain network involved in cognitive function. This finding generates the exciting hypothesis that a diet rich in vitamin C might play a supportive role in maintaining brain health and mitigating age-related cognitive decline in older adults,” Dr Tomohiro Shintaku at Hirosaki University, Japan said.
“It truly highlights the potential impact of our everyday dietary habits on our brain structures.”
For the study, published in the journal PLOS One, researchers at Hirosaki University, Japan analysed magnetic resonance imaging (MRI) scans and plasma vitamin C levels of 2,044 Japanese adults over the age of 64.
They measured each participant’s gray and white brain matter and evaluated connectivity in the default mode network, which is associated with attention and autobiographical memory.
After accounting for factors such as age, activity levels and education level, researchers found that participants with lower plasma vitamin C levels tended to have lower gray matter volume, as well as lower connectivity within the default mode network.
These findings suggest vitamin C could support cognitive function and counteract cognitive decline. But the findings only showed an association between vitamin C levels and brain health and not cause and effect.
“Dementia is the UK’s biggest killer, and we understand people are always looking for ways to reduce their risk of the condition,” Dr Richard Oakley, Associate Director of Research and Innovation at Alzheimer’s Society told the Independent.
He added: “This study does add to evidence linking nutritional intake with brain health, but it did not look at dementia symptoms or whether people involved in the study went on to develop dementia. As it looked at people at one point in time, it is difficult to know whether Vitamin C caused the brain differences or whether other factors, such as overall diet or health played a role.
“The Lancet Commission, which was part funded by Alzheimer’s Society, found nearly half of dementia cases globally are linked to modifiable risk factors – things that can be changed either on an individual or societal level – and managing these risk factors could potentially reduce dementia risk. This includes eating a healthy and balanced diet, including fruit and vegetables, which is also one part of supporting overall brain health.”
