Low vitamin C levels may reveal subtle changes in the brain

A Japanese research team reports that lower blood vitamin C levels may reflect subtle structural changes in the brain. Using data from 2,044 older adults, most in their late 60s and early 70s, the study paired a single high-resolution brain scan per participant with a fasting morning blood test for vitamin C. Led by radiologist Shingo Kakeda, M.D., the work found that people with lower vitamin C tended to have less gray matter relative to skull size. The association held after accounting for age, sex, education, blood pressure, diabetes, and lifestyle. The researchers also linked vitamin C to the default mode network, a set of brain regions active at rest and disrupted in conditions such as Alzheimer’s, mild cognitive impairment, and depression, with vitamin C correlating with how “sturdy” parts of the network appeared. The effect was described as modest.