The current Dietary Reference Intake (DRI), established in 1998, is 450 mg/day for pregnant women, although it is noted in the DRI documentation that “data were not sufficient” for deriving a true requirement and that “the estimate is uncertain,” and may be revised when more data become available.1 Several studies have been conducted since then, the most recent of which was published in The American Journal of Clinical Nutrition which suggests that the current DRI may be suboptimal during pregnancy.2
Researchers from Cornell University studied healthy third-trimester pregnant and non-pregnant women who were randomly assigned to receive either 480 or 930 mg choline/day for 12 weeks. Choline was obtained both from the diet (primarily from eggs) and a supplement. During the last 6 weeks of the study, a special stable isotope form of choline was provided, which allowed the investigators to track choline metabolism in the participants as well as in the fetus by studying placenta tissue and cord blood following delivery.
Results showed that there was a substantial demand for choline during pregnancy, as predicted. However, in those women consuming 930 mg choline/day, biomarkers of placental function and levels of the stress hormone cortisol in cord blood were improved compared to those consuming 480 mg choline/day. Further, several functions of choline were maximized in women consuming the higher versus the lower dosage, leading the scientists to conclude that “current recommendations may be suboptimal” during pregnancy.
Dietary choline is one of several nutritional factors associated with the occurrence of neural tube defects during pregnancy. Although folate intake from foods and supplements is well known to reduce the risk of a pregnancy being affected by neural tube defects, choline and methionine may also be important independent of folate intake. One study found that women consuming low levels of dietary choline have four times the risk of giving birth to a child with a neural tube defect.3
Although the majority of choline consumed in the aforementioned study was derived from supplements, dietary sources can also contribute to total choline intake, as well as provide other essential nutrients important during pregnancy. While dietary choline is found in a wide variety of foods, many foods do not have high quantities of the nutrient. Eggs have one of the highest amounts of choline of any food, providing 147 mg/large egg.
Whether findings from this study and others will lead to a re-visitation of the choline DRI for pregnant women remains to be determined.
1. IOM (Institute of Medicine). 1998. Thiamin, Riboflavin, Niacin, Vitamin B6, Folate, Vitamin B12, Pantothenic Acid, Biotin, and Choline. Washington, DC: The National Academies Press.
2. Yan J, Jiang X, West AA, Perry CA, Malysheva OV, Brenna JT, Stabler SP, Allen RH, Gregory JF 3rd, Caudill MA. Pregnancy alters choline dynamics: results of a randomized trial using stable isotope methodology in pregnant and nonpregnant women. Am J Clin Nutr. 2013;98:1459-67.
3. Shaw GM, Carmichael SL, Yang W, Selvin S, Schaffer DM. Periconceptional dietary intake of choline and betaine and neural tube defects in offspring. Am J Epidemiol. 2004;160:102-9.