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Vitamin B12 and folate bioavailability from two prenatal multivitamin/multimineral supplements
E B Dawson1, D R Evans, M E Conway
1Department of Obstetrics & Gynecology, The University of Texas Medical Branch at Galveston, 77555-0587, USA.
American Journal of Perinatology
|October 21, 2000
Summary
Prenatal vitamin absorption of B12 and folate is significantly higher when taken on an empty stomach compared to after a meal. Fasting enhances the bioavailability of these essential vitamins for pregnant women.
Area of Science:
- Nutritional Science
- Maternal Health
- Pharmacokinetics
Background:
- Adequate intake of Vitamin B12 and folate is crucial during pregnancy for fetal development and maternal health.
- Prenatal supplements are commonly used to ensure sufficient nutrient levels, but their absorption efficiency can vary.
- Understanding the impact of meal timing on vitamin absorption is important for optimizing prenatal nutrition strategies.
Purpose of the Study:
- To compare the bioavailability of Vitamin B12 and folate from two prenatal supplements (Stuartnatal Plus and Materna) versus a placebo in pregnant women.
- To investigate the effect of fasting versus postprandial state on the absorption of these vitamins.
- To determine the absorption kinetics, including peak absorption time and total body absorption rates.
Main Methods:
- A crossover, single-blind study involving 30 pregnant women.
- Administration of two prenatal multivitamin/multimineral supplements and a placebo.
- Blood samples collected at baseline and at 1, 3, 6, and 8 hours post-supplementation.
- Serum vitamin levels measured by radioimmunoassay to calculate total body absorption.
Main Results:
- The absorption peak for both Vitamin B12 and folate occurred at 3 hours post-ingestion.
- Total body absorption of both vitamins was significantly greater when supplements were taken while fasting compared to postprandially.
- Stuartnatal Plus showed 30% greater B12 absorption and 117% greater folate absorption when fasting versus Materna.
- Materna showed 33% greater B12 absorption and 57% greater folate absorption when fasting versus placebo.
Conclusions:
- Both Vitamin B12 and folate are rapidly absorbed within 3 hours into the maternal circulation.
- Fasting significantly enhances the absorption of Vitamin B12 and folate from prenatal supplements compared to postprandial intake.
- The choice of prenatal supplement may influence the degree of vitamin absorption, with both tested supplements demonstrating effective absorption when taken under optimal (fasting) conditions.
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