Clinical Trial: Relative Bioavailability of Iron and Folic Acid in New Test Supplement

Study Status: Completed
Recruit Status: Completed
Study Type: Interventional

Official Title: Relative Bioavailability of Iron and Folic Acid From a New Powdered Supplement Compared to a Traditional Tablet in Pregnant Women

Brief Summary: Deficiencies of iron and folic acid during pregnancy can lead to adverse outcomes for the fetus, thus supplements are recommended. Adherence to current tablet-based supplements is documented to be poor. Recently a powdered form of micronutrients has been developed which may decrease side-effects and thus improve adherence. However, before testing the efficacy of the supplement as an alternate choice for supplementation during pregnancy, the bioavailability of the iron needs to be determined. The objective of this study is to measure the relative bioavailability of iron and folic acid from a powdered supplement that can be sprinkled on semi-solid foods or beverages versus a traditional tablet supplement in pregnant women.

Detailed Summary:

Background:

The proposal addresses the issue of the bioavailability of the supplement SuppleFem as compared to the current standard supplement Materna during pregnancy in Canadian women. In recognition of the difficulties Canadian women face in order to meet their iron (27 mg/day) and folic acid (600 µg/day) requirements from dietary sources alone during pregnancy, Health Canada currently recommends that an iron/folic acid supplement be taken by all women during pregnancy. However, because of issues related to adherence, many pregnant women do not fulfill the Health Canada recommendation. Adherence is largely influenced by the gastrointestinal side-effects associated with the use of iron tablets or pills, as well as the nausea and vomiting common during the first trimester. It is estimated that approximately10% of women discontinue the use of iron because of adverse effects while others use less than a daily dose. Women suffering from indigestion and heart-burn (gastro-esophageal acid reflux) associated with the use of iron supplements commonly discontinue their use and many find it difficult to swallow pills when nauseated.

The bioavailabilities of iron and folic acid in supplements may be an area of concern, primarily due to the higher requirements during pregnancy. Materna® contains a large quantity of calcium (250 mg), whereas Sprinkles contains none. A study by Hallberg, et al. (1991) showed that adding as little as 165 mg of calcium to a meal reduced the absorption of iron by 50-60% in wheat rolls. In addition, a study by Koren, et al. (2004) showed that after adjusting for dose, the iron absorbed from one maternal iron supplement containing calcium was statistically less as compared to one without calcium. A study by Rossander-Hultén et al (1991, as cited by Sandröm, 2001) found that zinc has the
Sponsor: University of Toronto

Current Primary Outcome: The primary outcome is a comparison of area under the curve (AUC) for change in serum iron for each intervention adjusted for diurnal variation. The use of AUC will provide a single outcome for each participant. [ Time Frame: 3 weeks ]

Original Primary Outcome: Same as current

Current Secondary Outcome: The secondary outcome is a comparison of area under the curve (AUC) for change in serum folate for each intervention [ Time Frame: 2 weeks ]

Original Secondary Outcome: Same as current

Information By: University of Toronto

Dates:
Date Received: November 12, 2008
Date Started: October 2005
Date Completion:
Last Updated: November 12, 2008
Last Verified: November 2008