Midlife Vitamin D Levels Linked to Long-Term Brain Health

Wed, 08 Apr 2026 16:58:00 +0200

A new long-term study published in Neurology Open Access suggests that the amount of vitamin D a person has in their 30s and 40s may be connected to future brain health. Conducted by researchers at the University of Galway and supported by several international health agencies, the research followed 793 adults with an average age of 39 who were free of dementia. Participants’ blood samples were analyzed to measure vitamin D levels, and after 16 years, their brains were scanned to assess levels of tau and amyloid beta proteins, both markers associated with Alzheimer’s disease. The study found that participants with higher vitamin D concentrations—above 30 nanograms per milliliter—had lower levels of tau protein later in life. However, vitamin D did not show any significant correlation with amyloid beta levels. Only 5% of participants reported taking vitamin D supplements, and 34% had low levels at the start of the study. While the findings show a clear association, researchers caution t