# Vitamin D and cognition

1 paper in the library, strongest Strong.

**Graded Strong**: Twelve-month randomized, double-blind, placebo-controlled trial in 360 older adults with MCI, with near-complete follow-up of 355 participants, though still a single trial awaiting replication.

## Papers (1)

- [Vitamin D3 Plus DHA Beat Either Alone for Memory in Older Adults With MCI](https://usa-longevity.com/en/research/vitamin-d3-plus-dha-beat-either-alone-for-memory-in-older-adults-with-mci) · Strong · n = 360 · 2026 · Nutrients

## How this map is computed

A mark's size is the number of papers we hold on that pairing. It is a count, not a weighting by study design or sample size.

The fill shows the strongest grade in the cell. One Strong paper among four Preliminary ones still fills it dark, so open the cell to see the rest.

Grades and verdicts are assigned by a named person, never by counting.

An empty cell is a finding: nobody in our library has run that trial yet.

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_Canonical: https://usa-longevity.com/en/evidence/vitamin-d/cognition · Part of Longevity Cities_