Impact of Vitamin D Supplementation during Lactation on Vitamin D Status and Body Composition of Mother-Infant Pairs: A MAVID Randomized Controlled Trial

PLoS ONE

Sep 2014

DOI: 10.1371/journal.pone.0107708

Citations:34

Influential Citations:3

Interventional (Human) Studies

Enhanced Details

Methods

Design: prospective, double-blind, randomized, controlled trial conducted in four Warsaw hospitals. Participants: 174 healthy, term-delivery Caucasian mothers and their healthy term infants, followed for 6 months of lactation; baseline maternal age ~30 years (range 27-33); visits at baseline (within 3 weeks after delivery), 3 months, and 6 months; primary outcome: maternal serum 25(OH)D; data included serum 25(OH)D, iPTH, calcium, urinary Ca/Cr, and DXA; trial registered as NCT01506557; enrollment March 2011–April 2012.

Intervention

Mothers: two pills daily during 6 months of lactation: one prenatal multivitamin providing 400 IU vitamin D3 and 200 mg calcium, and one capsule providing 800 IU cholecalciferol or placebo; total daily vitamin D3: 1200 IU in the active group or 400 IU in the control group. Infants: vitamin D3 400 IU/d.

Results

Maternal 25(OH)D was similar at baseline and 3 months, but higher at 6 months with 1200 IU/d (25.6 ng/mL) vs 400 IU/d (23.1 ng/mL; P=0.009). Deficiency (<20 ng/mL) decreased more with 1200 IU/d: at 3 months 9% vs 25% (P=0.009); at 6 months 14% vs 30% (P=0.03). Infants’ 25(OH)D levels showed no intergroup differences; time increased infant levels but group differences were not significant. No intergroup differences in maternal or infant bone mass or body composition. Negative correlations between maternal 25(OH)D and maternal fat mass measures; higher maternal fat mass associated with lower 25(OH)D. Conclusion: 400 IU/d is insufficient to maintain maternal 25(OH)D >20 ng/mL; 1200 IU/d improves maternal vitamin D status but does not affect breastfed infant vitamin D status or maternal/infant bone mass or body composition over 6 months. Breastfed infants require vitamin D supplementation regardless of maternal intake; higher maternal doses or alternative strategies may be needed, with further dose-optimization research warranted.

Limitations

High dropout (137/174 completed primary outcome); differential compliance and education levels between groups; differences in exclusive breastfeeding rates; reliance on self-reported sun exposure and diet; study limited to Caucasian women in Poland; 6-month duration may limit detection of longer-term bone outcomes; results may not generalize to other populations or dosing regimens.

Abstract

Objective The optimal vitamin D intake for nursing women is controversial. Deterioration, at least in bone mass, is reported during lactation. This study evaluated whether vitamin D supplementation during lactation enhances the maternal and infant’s vitamin D status, bone mass and body composition. Design and Methods After term delivery, 174 healthy mothers were randomized to receive 1200 IU/d (800 IU/d+400 IU/d from multivitamins) or 400 IU/d (placebo+400 IU/d from multivitamins) of cholecalciferol for 6 months while breastfeeding. All infants received 400 IU/d of cholecalciferol. Serum 25-hydroxyvitamin D [25(OH)D], iPTH, calcium, urinary calcium, and densitometry were performed in mother-offspring pairs after delivery, and at 3 and 6 months later. Results A total of 137 (79%) (n = 70; 1200 IU/d, n = 67; 400 IU/d) completed the study. 25(OH)D was similar in both groups at baseline (13.7 ng/ml vs. 16.1 ng/ml; P = 0.09) and at 3 months (25.7 ng/ml vs. 24.5 ng/ml; P = 0.09), but appeared higher in the 1200 IU/d group at 6 months of supplementation (25.6 ng/ml vs. 23.1 ng/ml; P = 0.009). The prevalence of 25(OH)D <20 ng/ml was comparable between groups at baseline (71% vs. 64%, P = 0.36) but lower in the 1200 IU/d group after 3 months (9% vs. 25%, P = 0.009) and 6 months (14% vs. 30%, P = 0.03). Maternal and infants’ iPTH, calciuria, bone mass and body composition as well as infants’ 25(OH)D levels were not significantly different between groups during the study. Significant negative correlations were noted between maternal 25(OH)D and fat mass (R = −0.49, P = 0.00001), android fat mass (R = −0.53, P = 0.00001), and gynoid fat mass (R = −0.43, P = 0.00001) after 6 months of supplementation. Conclusions Vitamin D supplementation at a dose of 400 IU/d was not sufficient to maintain 25(OH)D >20 ng/ml in nursing women, while 1200 IU/d appeared more effective, but had no effect on breastfed offspring vitamin D status, or changes in the bone mass and the body composition observed in both during breastfeeding. Trial Registration ClinicalTrials.gov NCT01506557 show less