Alzheimers Dement

Higher midlife vitamin B12 levels linked to slower cognitive decline

November 10, 2025

Study details: A prospective analysis from the Framingham Heart Study included 1,994 dementia-free adults (mean age, 60) with at least two measures of a composite vitamin B₁₂ indicator (3cB₁₂) and repeated neuropsychological assessments. Linear mixed effects models estimated annual cognitive changes across quartiles of B₁₂ status, adjusting for relevant confounders. The interaction with folate status was also evaluated.

Results: Participants in the highest 3cB₁₂ quartile experienced significantly slower declines in memory (β, 0.0071), executive function (β, 0.0056), and language (β, 0.0090) compared with those in the lowest quartile executive function. Over 10 years, this corresponded to 0.05–0.09 standard deviation less cognitive decline. The association was largely consistent regardless of folate status, though memory benefits were most robust in those with elevated folate.

Clinical impact: These findings suggest that maintaining higher vitamin B₁₂ status from midlife onward may help mitigate age-related cognitive decline. Monitoring and optimizing B₁₂, especially in older adults, could be a practical strategy to preserve cognitive function into later life.

Source:

Marino FR, et al. (2025, October 28). Alzheimers Dement. Higher vitamin B₁₂ from mid- to late life is related to slower rates of cognitive decline. https://pubmed.ncbi.nlm.nih.gov/41152187/