title: Zinc supplementation does not alter plasma homocysteine, vitamin B12 and red blood cell folate concentrations in French elderly subjects.
abstract: OBJECTIVE
  In ageing, low folates and vitamin B12 status are frequent and can explain the increase of plasma homocysteine level. Zinc is involved in the folates and vitamin B12 metabolism with opposite actions. The aim of this study was to investigate the effects of zinc supplementation on homocysteine and vitamin B12 plasma levels as well as red blood cell folate level in French ageing subjects participating in the ZENITH study.
  
  
  METHODS
  Apparently healthy middle-aged (55-70 years) and free-living older (70-85 years) subjects were enrolled. They were randomly allocated to three groups: 0, 15 or 30 mg Zn per day for 6 months as zinc gluconate in addition to their usual dietary intake.
  
  
  RESULTS
  At baseline, plasma homocysteine levels (15.2+/-3.5 micromol/L) in older people were higher than in the middle-aged subjects (12.7+/-2.7 micromol/L) and was negatively correlated with vitamin B12 values (p=0.0036, r=-0.215) and with RBC folate levels (p<0.0001, r=-0.30). These results are in agreement with previous data. However, we found no correlation between the biomarkers of zinc status and homocysteine, vitamin B12 or folate levels at baseline. Moreover, 6-month zinc supplementation did not modify homocysteine, vitamin B12 and RBC folate values in either of the groups.
  
  
  CONCLUSIONS
  Zinc supplementation at moderate doses do not lead to deleterious effect on folate or vitamin B12 status in ageing healthy free-living people, but does not have any beneficial effects on homocysteine metabolism either.
authors.affiliation: Département de Biologie Intégrée, CHU de Grenoble, Grenoble F-38043, France. VDucros@chu-grenoble.fr
authors.forename: Véronique
authors.initials: V
authors.lastname: Ducros
authors.forename: Maud
authors.initials: M
authors.lastname: Andriollo-Sanchez
authors.forename: Josiane
authors.initials: J
authors.lastname: Arnaud
authors.forename: Nathalie
authors.initials: N
authors.lastname: Meunier
authors.forename: François
authors.initials: F
authors.lastname: Laporte
authors.forename: Isabelle
authors.initials: I
authors.lastname: Hininger-Favier
authors.forename: Charles
authors.initials: C
authors.lastname: Coudray
authors.forename: Monique
authors.initials: M
authors.lastname: Ferry
authors.forename: Anne-Marie
authors.initials: AM
authors.lastname: Roussel
mesh_terms: D000367:Age Factors; D000368:Aged; D019587:Dietary Supplements; D004912:Erythrocytes / Q000737:chemistry; D005260:Female; D005492:Folic Acid / Q000097:blood*; D005602:France; D006710:Homocysteine / Q000097:blood*; D006801:Humans; D008297:Male; D008875:Middle Aged; D014805:Vitamin B 12 / Q000097:blood*; D015032:Zinc / Q000008:administration & dosage*
chemical_list: D006710:Homocysteine; D005492:Folic Acid; D015032:Zinc; D014805:Vitamin B 12