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Bioavailability of Folate From a Mixed Diet Using a Stable Isotope Method

This study has been completed.
Wageningen University
Information provided by:
Wageningen University Identifier:
First received: August 12, 2005
Last updated: October 3, 2005
Last verified: August 2005

The main objectives of this project are:

  1. to determine the relative bioavailability of dietary folate from a total diet, compared with synthetic folic acid and
  2. to determine the bioavailability with a higher precision than previous methods.

The hypothesis is that the bioavailability of dietary folate within a confidence interval of +/-20% can be estimated.

Condition Intervention
Folate Bioavailability Healthy Behavioral: Controlled diet Behavioral: folic acid supplement Behavioral: 13C11-labelled folic acid supplement

Study Type: Interventional
Study Design: Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Double
Primary Purpose: Prevention
Official Title: The Relative Bioavailability of Folate From a Mixed Diet Compared to Synthetic Folic Acid Using a Stable Isotope Method

Resource links provided by NLM:

Further study details as provided by Wageningen University:

Primary Outcome Measures:
  • Bioavailability based on change in labelled folate concentration in plasma;
  • Bioavailability based on change in folate concentration in plasma

Secondary Outcome Measures:
  • Bioavailability based on change in concentration in plasma homocysteine

Estimated Enrollment: 75
Study Start Date: May 2005
Estimated Study Completion Date: June 2005
Detailed Description:
Folate plays a role in the prevention of certain birth defects and possibly also in prevention of neurocognitive diseases, cancer and cardiovascular disease. The proportion of dietary folate that is absorbed and becomes available for metabolic processes in the body has been estimated between 30 and 98%, but an accurate figure is lacking. Since subjects generally differ a lot in their folate or homocysteine response upon a change in dietary folate intake, the between-person variability in these responses is high. Therefore, bioavailability estimates derived from these responses have large confidence intervals. With this trial the researchers want to determine folate bioavailability with a higher precision than previous trials. A good estimate of folate bioavailability from the general diet is necessary to construct reliable dietary reference intakes for folate.

Ages Eligible for Study:   18 Years to 60 Years   (Adult)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   Yes

Inclusion Criteria:

  • Serum B12 >118pmol/L;
  • Serum creatinine <125micromol/L;
  • Plasma total homocysteine <26micromol/L.

Exclusion Criteria:

  • Cardiovascular disease, cancer, rheumatoid arthritis, epilepsy, gastro-intestinal disorders;
  • Use of drugs interfering with folate metabolism;
  • Use of B vitamins within the period three months prior to the study.
  • Body Mass Index (BMI) > 30
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Please refer to this study by its identifier: NCT00130585

Wageningen University
Wageningen, Netherlands, 6700EV
Sponsors and Collaborators
Wageningen Centre for Food Sciences
Wageningen University
Principal Investigator: Petra Verhoef, Dr. Wageningen Centre for Food Sciences
Principal Investigator: Martijn Katan, Professor Wageningen University
  More Information Identifier: NCT00130585     History of Changes
Other Study ID Numbers: A-007-RW
Study First Received: August 12, 2005
Last Updated: October 3, 2005

Keywords provided by Wageningen University:
Stable isotopes

Additional relevant MeSH terms:
Folic Acid
Vitamin B Complex
Growth Substances
Physiological Effects of Drugs processed this record on August 18, 2017