B-vitamins reduce plasma levels of beta amyloid

Neurobiol Aging. 2008 Feb;29(2):303-5. doi: 10.1016/j.neurobiolaging.2006.10.007. Epub 2006 Nov 20.


Elevated plasma homocysteine (tHcy) is a risk factor for Alzheimer's disease (AD), and thus B vitamins may have a role in the prevention of AD. The objective of this study was to determine if tHcy lowering vitamins decrease the circulating levels of A-beta protein 1-40 (A beta 40). We randomized 299 older men to treatment with 2mg of folate, plus 25mg of B6 and 400 microg of B12, or placebo. After 2 years of treatment the mean (S.E.) increase of A beta 40 was 7.0 pg/ml (8.4) in the vitamin group (4.9%), and 26.8 pg/ml (7.7) (18.5%) in the placebo group. We conclude that B vitamins may decrease the plasma level of A beta 40 and have a role in the prevention of AD.

Publication types

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

MeSH terms

  • Aged
  • Aged, 80 and over
  • Amyloid beta-Peptides / blood*
  • Double-Blind Method
  • Homocysteine / blood
  • Humans
  • Longitudinal Studies
  • Peptide Fragments / blood*
  • Vitamin B Complex / administration & dosage*
  • Vitamin B Complex / blood
  • Vitamin B Deficiency / blood
  • Vitamin B Deficiency / therapy*


  • Amyloid beta-Peptides
  • Peptide Fragments
  • amyloid beta-protein (1-40)
  • Homocysteine
  • Vitamin B Complex