A new study has found that adults with higher vitamin D levels in their 30s and 40s tend to have lower levels of tau protein in their brains about 16 years later. Tau is a key biomarker associated with dementia. The research, published this week, highlights a potential modifiable risk factor for brain health.
Researchers followed 793 adults who were around 39 years old on average and free of dementia at the study's start. They measured participants' blood vitamin D levels initially and conducted brain scans roughly 16 years later to assess tau and amyloid beta proteins, both linked to Alzheimer's disease. Levels above 30 nanograms per milliliter were deemed high, while those below were low; 34% of participants had low levels, and just 5% reported taking vitamin D supplements. After adjusting for age, sex, and depression symptoms, higher vitamin D was associated with lower tau levels, but not with amyloid beta.
