Japanese Study Finds Higher Vitamin C Levels Linked to Better Brain Connectivity in Older Adults

Researchers at Hirosaki University in Japan examined blood plasma vitamin C levels and brain MRI scans of 2,044 adults aged 64 and older. Participants with lower vitamin C showed reduced gray matter volume and weaker connectivity in the brain's default mode network, both early markers of cognitive decline.

The authors note the relationship is associative, not causal, and point to the role of vitamin C as an antioxidant that may protect neurons. They stress that a diet rich in vitamin‑C foods—such as citrus, bell peppers and leafy greens—could support brain health, while acknowledging limitations like a single blood draw and incomplete control of lifestyle factors.