Vitamin C & Long-Term Brain Health

A study out of Japan has linked getting enough vitamin C with changes in brain MRIs connected to memory and attention. Whereas prior research showed correlations between adequate vitamin C consumption and lowered rates of cognitive decline in older adults, these researchers wanted to investigate the relationship between Vitamin C blood levels and changes in brain structure. They looked at over 2,000 Japanese adults and found clear changes in gray matter of the brain on the MRIs.

Whether we’re thinking about our own brain health, that of a family-member, or that of our population as a whole, identifying as many factors as we can, especially simple ones like nutrition, is critical for prevention efforts. Many are already going down a path of decline, and we want to intervene sooner rather than later in order to see the greatest benefits. Rather than just adding more costly medicines and therapies that not everyone can get, we should look into simpler, more accessible interventions, like this one, that can really matter.

We should keep in mind, no pun intended, that correlation does not equal causation; nor does it guarantee efficacy of an intervention. This study, however, definitely points us in a good direction. Even when they factored out the effects of other influences on brain health (such as age, physical activity, and education level), they still found size differences in areas connected to attention and memory.

The gray matter of our brains are where the actual cells reside, mostly on the surface. These areas were larger when vitamin C levels were higher. The other area which showed a difference was in connectivity to the default mode network. While that sounds very fancy and complex, this area of the brain is just the part which runs background attention, self-memory, and awareness.

Further research needs to confirm whether increasing vitamin C intake will improve these brain areas, boosting their functions, and figure out the relevant mechanism of action. It is possible that it is not the vitamin C that matters but another substance that commonly comes with vitamin C intake. In that case, a vitamin C capsule would not help, but more citrus fruit probably would. It is possible that intake is not the only factor, too. Utilization or absorption could matter just as much, and variance in either could change the dosing an individual patient needs.

With a mechanism of action identified, we also might find other factors to optimize our brain health. These factors might work earlier or later in the progression of brain health decline and could be combined.

Regardless, in helping patients restore healthier, more abundant lives, we want to understand more and more about how nutrition interacts with our health. Knowledge leads to a clearer and more fruitful path, to lives which are lived longer and in good health.

 

Original Article:

Haruka Nagaya, Keita Watanabe, Tomohiro Shintaku, Miho Sasaki, Jusei Kudo, Sera Kasai, Yuka Ishimoto, Kana Saito, Shuichi Matsuhashi, Taiki Koshiishi, Mizuki Imura, Amo Ozawa, Saaya Mori, Daisuke Watanabe, Shin Shukunobe, Tatsuro Sasaki, Soichiro Tatsuo, Shinya Kakehata, Tatsuya Mikami, Daichi Kokubu, Yusuke Ushida, Shingo Kakeda. Plasma vitamin C levels are associated with brain structural networks on MRI: A large cohort study. PLOS One, 2026; 21 (6): e0348504 DOI: 10.1371/journal.pone.0348504

 

Thanks to Science Daily

PLOS. “Scientists discover a surprising link between vitamin C and brain health.” ScienceDaily. ScienceDaily, 1 July 2026. <www.sciencedaily.com/releases/2026/06/260626030428.htm>.

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Sanctuary Functional Medicine, under the direction of Dr Eric Potter, IFMCP MD, provides functional medicine services to Nashville, Middle Tennessee and beyond. We frequently treat patients from Kentucky, Alabama, Mississippi, Georgia, Ohio, Indiana, and more... offering the hope of healthier more abundant lives to those with chronic illness.