Effects of vitamin D supplementation on cognitive function and blood Aβ-related biomarkers in older adults with Alzheimer's disease: a randomised, double-blind, placebo-controlled trial

J Neurol Neurosurg Psychiatry. 2019 Dec;90(12):1347-1352. doi: 10.1136/jnnp-2018-320199. Epub 2019 Jul 11.


Objective: Our study aimed to assess the effect of a 12-month vitamin D supplementation on cognitive function and amyloid beta (Aβ)-related biomarkers in subjects with Alzheimer's disease (AD). METHODS : This was a randomised, double-blind, placebo-controlled trial. 210 AD patients were randomly divided into intervention and control groups. Participants received 12-month 800 IU/day of vitamin D or starch granules as placebo. Tests of cognitive performance and Aβ-related biomarkers were measured at baseline, 6 months and 12 months. RESULTS : Repeated-measures analysis of variance showed significant improvements in plasma Aβ42, APP, BACE1, APPmRNA, BACE1mRNA (p<0.001) levels and information, arithmetic, digit span, vocabulary, block design and picture arrange scores (p<0.05) in the intervention group over the control group. According to mixed-model analysis, vitamin D group had significant increase in full scale IQ during follow-up period (p<0.001).

Conclusions: Daily oral vitamin D supplementation (800 IU/day) for 12 months may improve cognitive function and decrease Aβ-related biomarkers in elderly patients with AD. Larger scale longer term randomised trials of vitamin D are needed.

Trial registration number: ChiCTR-IIR-16009549.

Keywords: Alzheimer’s disease; Aβpeptide; cognitive function; randomised controlled trial; vitamin D.

Publication types

  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aged
  • Alzheimer Disease / blood
  • Alzheimer Disease / drug therapy*
  • Alzheimer Disease / psychology
  • Amyloid Precursor Protein Secretases / blood
  • Amyloid beta-Protein Precursor / blood*
  • Aspartic Acid Endopeptidases / blood
  • Cognition / drug effects*
  • Dietary Supplements*
  • Double-Blind Method
  • Female
  • Humans
  • Hydroxycholecalciferols / blood
  • Intelligence Tests
  • Male
  • Neuropsychological Tests
  • Psychomotor Performance / drug effects
  • Vitamin D / therapeutic use*
  • Vitamins / therapeutic use*


  • APP protein, human
  • Amyloid beta-Protein Precursor
  • Hydroxycholecalciferols
  • Vitamins
  • Vitamin D
  • Amyloid Precursor Protein Secretases
  • Aspartic Acid Endopeptidases
  • BACE1 protein, human

Associated data

  • ChiCTR/ChiCTR-IIR-16009549