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Vitamin B12 Supplementation Study

This study has been completed.
Information provided by (Responsible Party):
USDA, Western Human Nutrition Research Center Identifier:
First received: January 16, 2009
Last updated: May 19, 2015
Last verified: May 2015
We hope to learn the clinical and functional signs of sub-clinical vitamin B12 deficiency and its response to supplementation in non-anemic, non-pregnant, and non-lactating women in Rural Mexico. Vitamin B12 is important in hematopoiesis, neuro-cognitive functions and genetic integrity. However vitamin B12 is only found in animal source foods therefore a large segment of the population in developing countries and those practicing vegetarianism are at risk of deficiency of the vitamin. This information will help decide weather supplementation with vitamin B12 is necessary in such populations for public health reasons.

Condition Intervention
Vitamin B12 Deficiency
Dietary Supplement: Vitamin B12
Dietary Supplement: placebo

Study Type: Interventional
Study Design: Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Double Blind (Participant, Care Provider, Outcomes Assessor)
Primary Purpose: Health Services Research
Official Title: Assessment of Functional Vitamin B12 Deficiency in Mexican Women

Resource links provided by NLM:

Further study details as provided by USDA, Western Human Nutrition Research Center:

Primary Outcome Measures:
  • response to B12 supplementation in serum B12, Methylmalonic acid, homocystein, and holotranscobalamin concentrations [ Time Frame: 0 and 3 mos ]

Secondary Outcome Measures:
  • DNA methylation change, and hematological response to B12 supplementation [ Time Frame: 0 and 3 mos ]

Enrollment: 180
Study Start Date: October 2004
Study Completion Date: November 2006
Primary Completion Date: August 2005 (Final data collection date for primary outcome measure)
Arms Assigned Interventions
Placebo Comparator: placebo
Receive placebo (sugar pill) during the intervention. Received a 1000 mg vitamin B12 injection at the end of the study.
Dietary Supplement: placebo
placebo given as a daily supplement 1000 mg injection of vitamin B12 given at the end of the study
Other Name: sugar pill
Active Comparator: Vitamin B12
Received 500 micrograms vitamin B12 per day during the study Received a 1000 mg vitamin B12 injection at the start of the study
Dietary Supplement: Vitamin B12
500 microgram daily supplement of vitamin B12 1000 mg injection vitamin B12 given at the start of the study


Ages Eligible for Study:   20 Years to 59 Years   (Adult)
Sexes Eligible for Study:   Female
Accepts Healthy Volunteers:   Yes

Inclusion Criteria:

  • Women age 20-59, apparently healthy, no severe B12 deficiency

Exclusion Criteria:

  • pregnancy, lactation, anemia and disease states
  Contacts and Locations
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Please refer to this study by its identifier: NCT00826657

Universidad Autonoma de Queretaro
Queretaro, Mexico
Sponsors and Collaborators
USDA, Western Human Nutrition Research Center
  More Information

Publications automatically indexed to this study by Identifier (NCT Number):
Responsible Party: USDA, Western Human Nutrition Research Center Identifier: NCT00826657     History of Changes
Other Study ID Numbers: 200412519-3
Study First Received: January 16, 2009
Last Updated: May 19, 2015

Keywords provided by USDA, Western Human Nutrition Research Center:
B12 deficiency
methylmalonic acid
vitamin B12 supplementation intervention

Additional relevant MeSH terms:
Vitamin B 12 Deficiency
Vitamin B Deficiency
Deficiency Diseases
Nutrition Disorders
Vitamin B 12
Vitamin B Complex
Growth Substances
Physiological Effects of Drugs
Hematinics processed this record on May 25, 2017