title: Weekly high-dose folic Acid supplementation is effective in lowering serum homocysteine concentrations in women.
abstract: OBJECTIVE
  To compare the efficacy of a weekly high-dose (2,800 microg) folic acid supplement with a daily (400 microg) folic acid supplement in lowering homocysteine concentrations in healthy women of childbearing age.
  
  
  METHODS
  Free-living healthy women of childbearing age (n = 138) were randomized to receive a weekly (2,800 microg), a daily (400 microg) folic acid supplement, or placebo. Blood samples were collected at baseline and at 12 weeks and analyzed for serum homocysteine and erythrocyte folate.
  
  
  RESULTS
  At 12 weeks the mean (95% CI) serum homocysteine concentrations declined significantly (p < 0.05) in women receiving the daily [week 12 - baseline: -1.4 (-2.0, -0.70) micromol/l] and the weekly supplement [-1.3 (-2.1, -0.5) micromol/l] versus placebo [0.0 (-0.5, 0.5) micromol/l]. There was no significant difference between the two folate-treated groups (p > 0.05). At 12 weeks the mean erythrocyte folate concentration increased significantly in both supplemented groups versus placebo (p < 0.001). The increase in erythrocyte folate was significantly greater (p < 0.001) in the daily group than in the weekly group [451 (380, 521) vs. 288 (240, 335) nmol/l].
  
  
  CONCLUSIONS
  A weekly high-dose folic acid supplement was as effective as a daily supplement in lowering homocysteine concentrations in healthy women of childbearing age. Further study is needed to determine if weekly folic acid supplementation is effective in lowering homocysteine concentrations in populations with high homocysteine.
authors.affiliation: Department of Human Nutrition, University of Otago, Dunedin, New Zealand.
authors.forename: Charlotte
authors.initials: C
authors.lastname: Adank
authors.forename: Timothy J
authors.initials: TJ
authors.lastname: Green
authors.forename: C Murray
authors.initials: CM
authors.lastname: Skeaff
authors.forename: Brooke
authors.initials: B
authors.lastname: Briars
mesh_terms: D000293:Adolescent; D000328:Adult; D019587:Dietary Supplements; D004311:Double-Blind Method; D004334:Drug Administration Schedule; D004912:Erythrocytes / Q000737:chemistry; D005260:Female; D005492:Folic Acid / Q000008:administration & dosage* / Q000097:blood*; D006710:Homocysteine / Q000097:blood* / Q000187:drug effects; D006801:Humans; D009436:Neural Tube Defects / Q000517:prevention & control; D016896:Treatment Outcome
chemical_list: D006710:Homocysteine; D005492:Folic Acid