Homocysteine, vitamin B12, folate and cognitive functions: a systematic and critical review of the literature

Vogel et al., 2009 | Int J Clin Pract | Systematic Review

Citation

Vogel T, Dali-Youcef N, ... Andrès E. Homocysteine, vitamin B12, folate and cognitive functions: a systematic and critical review of the literature. Int J Clin Pract. 2009-Jul;63(7):1061-7. doi:10.1111/j.1742-1241.2009.02026.x

Abstract

Elevated serum homocysteine, decreased folate and low vitamin B(12) serum levels are associated with poor cognitive function, cognitive decline and dementia. Despite evidence of an epidemiological association, randomised controlled trials did not provide any clear evidence so far that supplementation with vitamin B(12) and/or folate improves dementia or slows cognitive decline, even though it might normalise homocysteine levels. In this report, we review the current knowledge on the relationship between homocysteine, folate and vitamin B(12) levels and the way their disruption influences cognitive function in adults.

Key Findings

In this report, we review the current knowledge on the relationship between homocysteine, folate and vitamin B(12) levels and the way their disruption influences cognitive function in adults.

Outcomes Measured

Requires manual extraction

Population

Field	Value
Population	See abstract
Sample Size	See abstract
Age Range	See abstract
Condition	cognitive

MeSH Terms

Adult
Clinical Trials as Topic
Cognition Disorders
Cross-Sectional Studies
Dietary Supplements
Folic Acid
Homocysteine
Humans
Longitudinal Studies
Vitamin B 12
Vitamin B 12 Deficiency
Vitamin B Complex

Evidence Classification

Level: Systematic Review
Publication Types: Journal Article, Research Support, Non-U.S. Gov't, Systematic Review
Vertical: vitamin-b12-cognition

Provenance

PMID: 19570123
DOI: 10.1111/j.1742-1241.2009.02026.x
PMCID: Not in PMC
Verified: 2026-04-09 via PubMed E-utilities API

Source extracted via PubMed E-utilities API on 2026-04-09