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Efficacy of Weekly Versus Daily Folic Acid Supplementation

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ClinicalTrials.gov Identifier: NCT00394862
Recruitment Status : Completed
First Posted : November 1, 2006
Last Update Posted : April 2, 2012
Information provided by (Responsible Party):

Study Description
Brief Summary:
Investigate the efficacy of weekly versus daily of folic acid supplementation on improving folate, vitamin B12,

Condition or disease Intervention/treatment
Neural Tube Defects Drug: multivitamin

Detailed Description:

460 women of a rural community in the western highlands of Guatemala were recruited for participation in the double-blinded study led by Emory University and the Institute of Nutrition of Central America and Panama (INCAP). The women were randomly assigned one of 4 vitamin treatments containing different levels of folic acid, Vitamin B12, iron and zinc. The treatments were as follows:

  1. weekly dose of folic acid at 5000ug, iron at 120 mg, zinc at 30mg, and B12 at 16.8 ug;
  2. weekly dose of folic acid at 2800ug, iron at 120mg, zinc at 0mg and B12 at 16.8ug;
  3. daily dose of folic acid at 400ug, iron at 60mg, zinc at 15mg, B12 at 2.4ug; and
  4. daily dose of folic acid at 200ug, iron at 50mg, zinc at 0mg, and B12 at 2.4ug.

The women, aged 15-49, received the vitamins daily for 3 months. Anthropometric data and blood samples were taken at baseline and post-supplementation. The participants also completed a series of dietary interviews at baseline and post-intervention. No pregnant or lactating mothers were admitted into the study, nor severely anemic females. Blood samples were sent to the National Laboratory in Cuernavaca, Mexico, for analysis of serum folate levels.

Study Design

Study Type : Interventional  (Clinical Trial)
Estimated Enrollment : 460 participants
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Double
Primary Purpose: Prevention
Study Start Date : January 2006
Primary Completion Date : June 2006
Study Completion Date : July 2006

Resource links provided by the National Library of Medicine

U.S. FDA Resources

Arms and Interventions

Outcome Measures

Primary Outcome Measures :
  1. serum folate level
  2. red blood cell folate

Secondary Outcome Measures :
  1. homocysteine
  2. ferritin
  3. serum zinc
  4. serum B12
  5. blood pressure
  6. depression

Eligibility Criteria

Information from the National Library of Medicine

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Ages Eligible for Study:   15 Years to 49 Years   (Child, Adult)
Sexes Eligible for Study:   Female
Accepts Healthy Volunteers:   Yes

Inclusion Criteria:

  • female
  • aged 15-49

Exclusion Criteria:

  • pregnant
  • lactating less than 3 months
  • severely anemic
Contacts and Locations

Information from the National Library of Medicine

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.

Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT00394862

Sponsors and Collaborators
Emory University
Centers for Disease Control and Prevention
Principal Investigator: Reynaldo Martorell, PHD, MPH Emory University
More Information

Responsible Party: Dr. Reynaldo Martorell, Professor, Emory University
ClinicalTrials.gov Identifier: NCT00394862     History of Changes
Other Study ID Numbers: 205-2004
First Posted: November 1, 2006    Key Record Dates
Last Update Posted: April 2, 2012
Last Verified: March 2012

Additional relevant MeSH terms:
Neural Tube Defects
Spinal Dysraphism
Nervous System Malformations
Nervous System Diseases
Congenital Abnormalities