Document Detail


Long-term effects of folic acid fortification and B-vitamin supplementation on total folate, homocysteine, methylmalonic acid and cobalamin in older adults.
MedLine Citation:
PMID:  19009931     Owner:  NLM     Status:  MEDLINE    
Abstract/OtherAbstract:
OBJECTIVE: To investigate the long-term effects of the Canadian folic acid fortification program in older adults' whole blood cell folate (folate) and cobalamin (Cbl) status, including homocysteine (tHcy) and methylmalonic acid (MMA), with and without voluntary B-vitamin intake, from 1997 to 2004. METHODS: Cohort of community-dwelling volunteer older adults. Clinical and biochemical data, including intake of B-vitamin supplements, were obtained at 2- to 2.5-year intervals and divided in 4 periods. Random coefficients (mixed effects) models were used to estimate the linear trend in folate and to compare levels of biochemical parameters between periods. All models were estimated by restricted maximum likelihood as implemented in PROC MIXED of SAS V8.2. RESULTS: Folate levels increased continuously at a yearly rate of 234 ng/mL (95% CI 213-254; p < 0.001) and had not plateaued by the last period when 84% of subjects without B-vitamins had elevated folate. Homocysteine did not remain suppressed. Elevated tHcy was as prevalent in the last study period as in the first. No significant deficits of Cbl or increases of MMA were observed, but MMA levels tended to increase with time in subjects without B-vitamins. B-vitamin supplements significantly affected all results, reducing tHcy and MMA levels. CONCLUSION: In this population, fortification with folic acid has resulted in cumulative increases of folate with no long-term reduction in tHcy or changes in Cbl or MMA. Possible deleterious effects of cumulative increases of folate, and beneficial effects of B-vitamin supplements in reducing tHcy and MMA, should be investigated.
Authors:
Angeles A Garcia; Andrew G Day; Katherine Zanibbi; Maria Victoria Zunzunegui
Publication Detail:
Type:  Journal Article; Research Support, Non-U.S. Gov't    
Journal Detail:
Title:  Canadian journal of public health. Revue canadienne de santé publique     Volume:  99     ISSN:  0008-4263     ISO Abbreviation:  Can J Public Health     Publication Date:    2008 Sep-Oct
Date Detail:
Created Date:  2008-11-17     Completed Date:  2009-01-06     Revised Date:  -    
Medline Journal Info:
Nlm Unique ID:  0372714     Medline TA:  Can J Public Health     Country:  Canada    
Other Details:
Languages:  eng     Pagination:  428-33     Citation Subset:  IM    
Affiliation:
Department of Medicine, Queen's University, Kingston, ON. garciaa@providencecare.ca
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MeSH Terms
Descriptor/Qualifier:
Aged
Aged, 80 and over
Canada
Dietary Supplements*
Female
Folic Acid / administration & dosage*,  blood*
Homocysteine / blood*
Humans
Male
Methylmalonic Acid / blood*
Time Factors
Vitamin B 12 / blood*
Vitamin B Complex / administration & dosage*
Chemical
Reg. No./Substance:
12001-76-2/Vitamin B Complex; 454-28-4/Homocysteine; 516-05-2/Methylmalonic Acid; 59-30-3/Folic Acid; 68-19-9/Vitamin B 12

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine


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