Researchers in Japan have identified an association between higher blood levels of vitamin C and greater gray matter volume plus stronger connectivity in a key brain network among adults over age 64.
The observational study examined MRI scans and plasma samples from 2,044 participants. Lower vitamin C concentrations correlated with reduced gray matter and weaker default mode network connections after adjustments for age, education and physical activity.
Led by Haruka Nagaya of Hirosaki University, the research appeared on June 10, 2026, in PLOS ONE. It builds on prior evidence linking dietary vitamin C intake to cognitive outcomes but stops short of proving causation.
Tomohiro Shintaku noted the findings generate the hypothesis that a vitamin C-rich diet might support brain health and mitigate age-related decline. The team called for further studies tracking levels over time across diverse populations.
Support came from KAGOME CO., LTD. and grants by the Japan Agency for Medical Research and Development.
