Despite both delivery forms producing equivalent increases in blood levels of folic acid, capsules were slower to increase blood levels, according to results published in the Journal of the Academy of Nutrition and Dietetics.
“Because only approximately 50% of women of reproductive potential plan their pregnancies, it is recommended that practitioners work with women of reproductive potential to ensure their daily folic acid intake from fortified foods and/or supplements meets the level recommended for reducing the risk of neural tube defect–affected pregnancy,” explained the researchers, led by Kevin Maki from Biofortis-Provident Clinical Research.
“The results from this investigation provide important information to practitioners who commonly recommend folic acid supplements for pregnant women and women of reproductive potential.”
The study provided about 1,000 micrograms of folic acid in tablet form (Nature Made) or about 1,000 micrograms of folic acid in a multivitamin plus DHA softgel capsule (Nature Made), and the study was funded by Pharmavite, LLC.
Benefits for babies
An overwhelming body of evidence links has linked folate deficiency in early pregnancy to increased risk of neural tube defects (NTD) - most commonly spina bifida and anencephaly - in infants.
This connection led to the 1998 introduction of public health measures in the US and Canada, where all grain products are fortified with folic acid - the synthetic, bioavailable form of folate.
Preliminary evidence indicates that the measure is having an effect with a reported 15 to 50 per cent reduction in NTD incidence. A total of 51 countries now have some degree of mandatory fortification of flour with folic acid.
Other countries are also considering such fortification measures: In the meantime, recommendations for women of child-bearing age to consume folic acid supplements continue.
The formulation of supplements, the presence of fillers, and the coatings used in various supplements is reported to affect the rate at which a product dissolves and releases its contents on passage through the gastrointestinal tract.
Pharmavite scientists, working with scientists from Biofortis-Provident Clinical Research in Glen Ellyn, IL, tested if the B vitamin was affected by formulating as part of a multivitamin with DHA in a softgel capsule, compared to a standard tablet.
The study involved 16 women aged between 18 and 45. The participants received a single dose of about 1,000 micrograms of folic acid tablet form (Nature Made) or about 1,000 micrograms of folic acid in a multivitamin plus DHA softgel capsule (Nature Made Prenatal Multi + DHA liquid).
Regular blood sample collection over an eight hour period revealed that average blood level increases did not differ between the two delivery forms. However, softgels resulted in a delayed time to reach the maximum level, with maximum levels observed 3.9 hours after consumption, compared to 1.7 hours for the tablet.
“Although approximately 1,000 micrograms of folic acid/day was tested, the recommended intake of folic acid in the periconceptional period is 400 micrograms/day; additional low-dose studies are needed to determine whether a lower dose would produce similar effects to those described here,” they concluded.
Source: Journal of the Academy of Nutrition and Dietetics
Published online ahead of print, doi: 10.1016/j.jand.2012.03.001
“Absorption of Folic Acid from a Softgel Capsule Compared to a Standard Tablet”
Authors: K.C. Maki, L.I. Ndife, K.M. Kelley, A.L. Lawless, J.R. Brooks, S.B. Wright, J.M. Shields, M.R. Dicklin