við Streym Susanna, Højskov Carsten S, Møller Ulla Kristine, Heickendorff Lene, Vestergaard Peter, Mosekilde Leif, Rejnmark Lars
Departments of Endocrinology and Internal Medicine and.
Clinical Biochemistry, Aarhus University Hospital, Aarhus, Denmark; and.
Am J Clin Nutr. 2016 Jan;103(1):107-14. doi: 10.3945/ajcn.115.115105. Epub 2015 Dec 16.
Parents are advised to avoid the direct sun exposure of their newborns. Therefore, the vitamin D status of exclusively breastfed newborns is entirely dependent on the supply of vitamin D from breast milk.
We explored concentrations of ergocalciferol (vitamin D2) and cholecalciferol (vitamin D3) (vitamin D) and 25-hydroxivitamin D2 plus D3 (25-hydroxyvitamin D [25(OH)D]) in foremilk and hindmilk during the first 9 mo of lactation and identified indexes of importance to the concentrations.
We collected blood and breast-milk samples from mothers at 2 wk (n = 107), 4 mo, (n = 90), and 9 mo (n = 48) postpartum. Blood samples from infants were collected 4 and 9 mo after birth. We measured concentrations of vitamin D metabolites in blood and milk samples with the use of liquid chromatography-tandem mass spectrometry.
Concentrations of vitamin D and 25(OH)D correlated significantly and were higher in hindmilk than in foremilk. Milk concentrations were also correlated with maternal plasma 25(OH)D concentrations. In foremilk and hindmilk, concentrations were a median (IQR) of 1.35% (1.04-1.84%) and 2.10% (1.63-2.65%), respectively, of maternal plasma 25(OH)D concentrations (P < 0.01). Milk concentrations showed a significant seasonal variation. Mothers who were taking vitamin D supplements had higher concentrations than did nonusers. Medians (IQRs) of infant daily intake through breast milk of vitamin D and 25(OH)D were 0.10 μg (0.02-0.40 μg) and 0.34 μg (0.24-0.47 μg), respectively, which were equal to a median (IQR) antirachitic activity of 77 IU/d (52-110 IU/d).
The supply of vitamin D from breast milk is limited. Exclusively breastfed infants received <20% of the daily dose recommended by the Institute of Medicine for infants during the first year of life. This trial was registered at clinicaltrials.gov as NCT02548520.
建议父母避免新生儿直接暴露于阳光下。因此，纯母乳喂养新生儿的维生素D状况完全取决于母乳中维生素D的供应。
我们探究了哺乳期前9个月初乳和后乳中麦角钙化醇（维生素D2）、胆钙化醇（维生素D3）（维生素D）以及25-羟维生素D2加D3（25-羟维生素D [25(OH)D]）的浓度，并确定了与这些浓度相关的重要指标。
我们在产后2周（n = 107）、4个月（n = 90）和9个月（n = 48）时收集了母亲的血液和母乳样本。在婴儿出生后4个月和9个月时收集其血液样本。我们使用液相色谱-串联质谱法测量血液和母乳样本中维生素D代谢物的浓度。
维生素D和25(OH)D的浓度显著相关，且后乳中的浓度高于初乳。母乳中的浓度也与母亲血浆25(OH)D浓度相关。在初乳和后乳中，浓度分别为母亲血浆25(OH)D浓度的中位数（IQR）1.35%（1.04 - 1.84%）和2.10%（1.63 - 2.65%）（P < 0.01）。母乳中的浓度呈现出显著的季节性变化。服用维生素D补充剂的母亲的母乳浓度高于未服用者。婴儿通过母乳每日摄入维生素D和25(OH)D的中位数（IQR）分别为0.10 μg（0.02 - 0.40 μg）和0.34 μg（0.24 - 0.47 μg），这相当于抗佝偻病活性的中位数（IQR）为77 IU/d（52 - 110 IU/d）。
母乳中维生素D的供应有限。纯母乳喂养的婴儿在生命的第一年获得的维生素D量低于美国医学研究所为婴儿推荐的每日剂量的20%。该试验在clinicaltrials.gov上注册，注册号为NCT02548520。
