2012 May 30 by Dr. Randy
A recent study of vitamin D levels in pregnant women has revealed a remarkable finding. Children born to women with a lower vitamin D level during pregnancy have increased body fat later in childhood compared to those children whose mothers have a higher vitamin D level.
A maternal vitamin D level less than 50 nmol/L was associated with increased fat mass in children at 4 and 6 years of age. Children in the study had an 8 percent reduction in fat mass if their mothers had a vitamin D level of 50-75 nmol/L. The mother’s own levels of fat (body mass index) did not have any effect on the study results. The authors suggest that vitamin D insufficiency during pregnancy may program the child to gain excess fat later in life. Other studies have also confirmed an association between vitamin D intake and fat mass in adults.
This study adds to the growing body of evidence that has found higher levels of health in children born to mothers with adequate vitamin D stores during pregnancy. A higher vitamin D level during pregnancy is associated with less respiratory problems in babies, and a higher cord blood vitamin D level also correlates with less allergies and respiratory infections.
Pregnant women should have their vitamin D levels checked repeatedly during pregnancy and take a vitamin D supplement to maintain blood levels between 75 and 100 nmol/L.
Sarah R Crozier, Nicholas C Harvey, Hazel M Inskip, Keith M Godfrey, Cyrus Cooper, Siân M Robinson, and the SWS Study Group. Maternal vitamin D status in pregnancy is associated with adiposity in the offspring: findings from the Southampton Women’s Survey. American Journal of Clinical Nutrition. 2012, doi: 10.3945/ajcn.112.037473 July 2012.
2012 April 9 by Dr. Randy
Vitamin D prevents language problems
A study published in the March 2012 issue of Pediatrics, the journal of the American Association of Pediatrics, has shown again how important vitamin D3 supplementation is during pregnancy (Whitehouse, 2012). This study measured the vitamin D level of pregnant women and then observed language development in their children at different ages (2, 5, 8, 10, 14, and 17 years of age).
The study found that women who had a vitamin D level less than 46 nmol/L during pregnancy were at least twice as likely to have children with language difficulties at ages 5 and 10 years compared to women with a vitamin D level of 70 nmol/L or higher.
This finding is especially interesting because most labs place the normal limit of serum 25(OH)-vitamin D in the 30 range, rather than the 70 range. Many vitamin D experts have said that a range of 60 to 100 is ideal, and this study suggests that at least during pregnancy these higher levels of vitamin D are ideal. In order to achieve these levels pregnant women need to take a significantly higher level of vitamin D3 than is found in most prenatal or calcium supplements. A supplement in the range of 5,000 to 10,000 IU of vitamin D3 daily is usually required to raise serum vitamin D levels to these levels.
Vitamin D prevents respiratory problems
Vitamin D taken during pregnancy has shown other benefits for later childhood as well. Several studies have shown that higher vitamin D levels during pregnancy are associated with less respiratory infections and asthma during childhood.
In a study published in the January 2011 issue of Pediatrics, the umbilical cord-blood level of vitamin D was evaluated at birth for 922 healthy newborns and these levels were compared to the incidence of respiratory infections, wheezing, and allergies over a 5 year period. The researchers discovered that low levels of vitamin D in cord-blood were associated with a higher risk of respiratory infections during the first months after birth and a higher risk of wheezing episodes throughout early childhood (Camargo, 2011). Twenty percent of the newborns in this study had a cord-blood level that indicated a deficiency of vitamin D (less than 25 nmol/L), and these babies had more infections and wheezing than infants with higher vitamin D levels.
Four previous studies published between 2006 and 2009 showed that the babies of mothers who ate foods high in vitamin D or took vitamin D supplements during pregnancy had a decreased incidence of wheezing and/or asthma (Erkkola, 2000; Miyake, 2010). This new study was the first to test the vitamin D level at birth and associate it with the occurrence of respiratory symptoms.
It was remarkable that a single low cord-blood level of vitamin D at birth would be associated with wheezing even several years later. The authors propose several possible reasons for this finding. Because vitamin D is essential for healthy immune system function, vitamin D may be necessary to initiate immune mechanisms while the baby is still in the womb or soon after birth.
Recommended supplements for pregnancy
Pregnant women should take a high quality prenatal vitamin/mineral supplement that contains folate. In addition during pregnancy it is important to take vitamin D, an omega-3 fatty acid supplement with DHA, and probiotics, all of which have proven to have positive health benefits for babies. Pregnant women should also have their vitamin D levels checked during pregnancy to ensure that they have achieved recommended levels of 70-100 nmol/L.
Camargo CA, et al. Cord-Blood 25-Hydroxyvitamin D Levels and Risk of Respiratory Infection, Wheezing, and Asthma. Pediatrics Vol. 127 No. 1 January 2011, pp. e180-e187.
Erkkola M, Kaila M, Nwaru BI, et al. Maternal vitamin D intake during pregnancy is inversely associated with asthma and allergic rhinitis in 5-year-old children. Clin Exp Allergy. 2009;39(6):875-882.
Miyake Y, Sasaki S, Tanaka K, Hirota Y. Dairy food, calcium and vitamin D intake in pregnancy, and wheeze and eczema in infants. Eur Respir J. 2010;35(6):1228-1234.
Whitehouse, AJO, et al. Maternal Serum Vitamin D Levels During Pregnancy and Offspring Neurocognitive Development. Pediatrics 2012; 129:3 485-493; published ahead of print February 13, 2012, doi:10.1542/peds.2011-2644