Lactating Canadian Women Consuming 1000 µg Folic Acid Daily Have High Circulating Serum Folic Acid Above a Threshold Concentration of Serum Total Folate.

Background: Consumption of high-dose folic acid supplements is common throughout pregnancy and lactation in several countries, including Canada, Brazil, and the United States, and may lead to high levels of circulating unmetabolized folic acid. Objective: The objective of the study was to characterize serum and whole-blood folate forms in Canadian lactating women regularly consuming a daily high-dose folic acid supplement. Methods: One-hundred and seventeen Canadian lactating women aged between 18 and 42 y, with a geometric mean ± SD prepregnancy body mass index (kg/m2) of 23.1 ± 1.2, were enrolled in a vitamin D supplementation trial between 13 and 22 wk of gestation. As part of the trial, the women received a daily multivitamin containing 1000 µg folic acid throughout pregnancy and lactation until 8 wk postpartum. At 8 wk postpartum, serum folate forms, including folic acid and RBC total folate, were determined from nonfasted blood samples. Differences in median folate vitamer concentrations among quintiles of serum total folate status were assessed by the Wald test and quantile regression methods. A breakpoint in the relation between serum folic acid and serum total folate was modeled with the use of the segmented package in R. Results: Median serum total folate concentration among participants was 79.3 nmol/L (5th-95th percentile 30.7-186 nmol/L) and median RBC folate concentration was 2790 nmol/L (5th-95th percentile 1330-4850 nmol/L). There was a breakpoint in the relation between serum total folate and serum folic acid at 78.5 nmol/L (95% CI: 67.9, 89.1 nmol/L), below which serum folic acid was not associated with serum total folate, and above which serum folic acid increased 0.78 nmol/L (95% CI: 0.70, 0.86 nmol/L; P < 0.001) for each 1 nmol/L increase in serum total folate. Conclusions: These data demonstrate the potential for high serum folic acid concentrations proportional to overall folate concentrations in lactating women with serum total folate >80 nmol/L taking high-dose supplemental folic acid. This study was registered at clinicaltrials.gov as NCT01112891.

Concentrations of Water-Soluble Forms of Choline in Human Milk from Lactating Women in Canada and Cambodia.

Choline has critical roles during periods of rapid growth and development, such as infancy. In human milk, choline is mostly present in water-soluble forms (free choline, phosphocholine, and glycerophosphocholine). It is thought that milk choline concentration is influenced by maternal choline intake, and the richest food sources for choline are of animal origin. Scarce information exists on milk choline from countries differing in animal-source food availability. In this secondary analysis of samples from previous trials, the concentrations of the water-soluble forms of choline were quantified by liquid chromatography-tandem mass spectrometry in mature milk samples collected from lactating women in Canada (n = 301) and in Cambodia (n = 67). None of the water-soluble forms of choline concentrations in milk differed between Canada and Cambodia. For all milk samples (n = 368), free choline, phosphocholine, glycerophosphocholine, and the sum of water-soluble forms of choline concentrations in milk were (mean (95%CI)) 151 (141, 160, 540 (519, 562), 411 (396, 427), and 1102 (1072, 1133) µmol/L, respectively. Theoretically, only 19% of infants would meet the current Adequate Intake (AI) for choline. Our findings suggest that the concentrations in milk of water-soluble forms of choline are similar in Canada and Cambodia, and that the concentration used to set the infant AI might be inaccurate.

Correlations between Maternal, Breast Milk, and Infant Vitamin B12 Concentrations among Mother-Infant Dyads in Vancouver, Canada and Prey Veng, Cambodia: An Exploratory Analysis.

Vitamin B12 plays an essential role in fetal and infant development. In regions where animal source food consumption is low and perinatal supplementation is uncommon, infants are at risk of vitamin B12 deficiency. In this secondary analysis, we measured total vitamin B12 concentrations in maternal and infant serum/plasma and breast milk among two samples of mother-infant dyads in Canada (assessed at 8 weeks post-partum) and in Cambodia (assessed between 3-27 weeks post-partum). Canadian mothers (n = 124) consumed a daily vitamin B12-containing multiple micronutrient supplement throughout pregnancy and lactation; Cambodian mothers (n = 69) were unsupplemented. The maternal, milk, and infant total vitamin B12 concentrations (as geometric means (95% CI) in pmol/L) were as follows: in Canada, 698 (648,747), 452 (400, 504), and 506 (459, 552); in Cambodia, 620 (552, 687), 317 (256, 378), and 357 (312, 402). The majority of participants were vitamin B12 sufficient (serum/plasma total B12 > 221 pmol/L): 99% and 97% of mothers and 94% and 84% of infants in Canada and Cambodia, respectively. Among the Canadians, maternal, milk, and infant vitamin B12 were all correlated (p < 0.05); only maternal and infant vitamin B12 were correlated among the Cambodians (p < 0.001).

Maternal vitamin D3 supplementation at 50 µg/d protects against low serum 25-hydroxyvitamin D in infants at 8 wk of age: a randomized controlled trial of 3 doses of vitamin D beginning in gestation and continued in lactation.

BACKGROUND: Vitamin D supplementation is recommended for breastfed infants. Maternal supplementation beginning in gestation is a potential alternative, but its efficacy in maintaining infant 25-hydroxyvitamin D [25(OH)D] concentration after birth is unknown. OBJECTIVES: We determined the effect of 3 doses of maternal vitamin D supplementation beginning in gestation and continued in lactation on infant serum 25(OH)D and compared the prevalence of infant serum 25(OH)D cutoffs (>30, >40, >50, and >75 nmol/L) by dose at 8 wk of age. DESIGN: Pregnant women (n = 226) were randomly allocated to receive 10, 25, or 50 µg vitamin D3/d from 13 to 24 wk of gestation until 8 wk postpartum, with no infant supplementation. Mother and infant blood was collected at 8 wk postpartum. RESULTS: At 8 wk postpartum, mean [nmol/L (95% CI)] infant 25(OH)D at 8 wk was higher in the 50-µg/d [75 (67, 83)] than in the 25-µg/d [52 (45, 58)] or 10-µg/d [45 (38, 52)] vitamin D groups (P < 0.05). Fewer infants born to mothers in the 50-µg/d group had a 25(OH)D concentration <30 nmol/L (indicative of deficiency) than infants in the 25- and 10-µg/d groups, respectively (2% compared with 16% and 43%; P < 0.05). Fewer than 15% of infants in the 10- or 25-µg/d groups achieved a 25(OH)D concentration >75 nmol/L compared with 44% in the 50-µg/d group (P < 0.05). Almost all infants (∼98%, n = 44) born to mothers in the 50-µg/d group achieved a 25(OH)D concentration >30 nmol/L. At 8 wk postpartum, mean maternal 25(OH)D concentration was higher in the 50-µg/d [88 (84, 91)] than in the 25-µg/d [78 (74, 81)] or 10-µg/d [69 (66, 73)] groups (P < 0.05). CONCLUSIONS: Maternal supplementation beginning in gestation with 50 µg vitamin D3/d protects 98% of unsupplemented breastfed infants against 25(OH)D deficiency (<30 nmol/L) to at least 8 wk, whereas 10 or 25 µg vitamin D/d protects only 57% and 84% of infants, respectively.