Midlife Vitamin D Linked to Lower Tau

Higher vitamin D levels in early midlife were tied to lower tau burden on later brain imaging, while no association was seen with amyloid.

By
Andrea Surnit
April 10, 2026
3 min

Conexiant

Objective:

To investigate the association between circulating vitamin D levels in early midlife and tau deposition on brain imaging in dementia-free adults.

Approach:

Key Findings:

Higher vitamin D levels were associated with lower global tau burden and lower tau burden in regions vulnerable to Alzheimer's disease.
No association was found between vitamin D levels and amyloid burden.
Findings remained consistent after excluding participants taking vitamin D supplements.

Interpretation:

The study suggests that higher serum vitamin D levels in early midlife may be linked to lower tau deposition, indicating a potential modifiable factor for preclinical Alzheimer's disease.

Limitations:

Predominantly White cohort limits generalizability.
Lack of repeated vitamin D measurements over time.
Long interval between blood sampling and brain imaging may lead to exposure misclassification.

Conclusion:

In dementia-free asymptomatic adults, higher serum 25-hydroxyvitamin D in early midlife was associated with lower tau deposition on brain imaging a mean of 16 years later.