This One Vitamin May Help Protect Your Brain From Dementia Years Later

A study of 793 adults found higher midlife vitamin D levels were associated with lower brain tau protein about 16 years later.

Researchers did not find a link between midlife vitamin D and brain amyloid beta levels.

Vitamin D was measured once at baseline and 34% of participants had low levels; only 5% reported taking supplements.

The study was published April 1, 2026 in Neurology Open Access and authors say the findings show association, not proof of causation.