Midlife Vitamin D Levels Linked to Lower Dementia Markers

Higher levels of vitamin D in midlife may be associated with a reduced risk of dementia-related brain changes, according to a study published in Neurology Open Access by the American Academy of Neurology. The research found that individuals with higher vitamin D levels had lower amounts of tau protein—a key marker linked to Alzheimer’s disease—years later.

Led by the researcher from the University of Galway, the study followed 793 adults over 16 years. Participants with vitamin D levels above 30 ng/mL showed fewer tau deposits in brain scans, even after adjusting for other factors. However, no link was found between vitamin D and amyloid beta levels.

While the findings suggest a potential protective role, researchers emphasise that the study shows association, not causation, and further research is needed to confirm the link.

12-04-2026