According to an article published in the Journal of Nutrition black and white pregnant women and neonates residing in the northern US are at high risk of vitamin D insufficiency, even when mothers are compliant with prenatal vitamins. The researchers evaluated 400 pregnant women and their newborn babies living in the Pittsburgh, PA, area to see if there were any seasonal or racial variations in their vitamin D status. Although over 90% of the women used prenatal vitamins, many of them were not getting enough vitamin D as measured by their serum Vitamin D levels. About 10% of white babies and almost 46% of black babies were serum vitamin D deficient, meaning that they were at risk for developing rickets.
It appears to me that this article has a couple of questionable shortcomings. For one the cutoff they used was less than 80 nmol/L of vitamin D when the accepted Vitamin D level cutoff is 37 nmol/L. So many of the mothers the authors state are vitamin D deficient would not be deficient in the eyes of other researchers. As we would expect the serum Vitamin D levels were highest in the fall and lowest in the spring. This is because the sun creates vitamin D. Therefore in the fall and winter we get little sun so our levels are lowest in the Spring since we are sun starved for 6 months. The fall being the highest since our bodies have been making Vitamin D from April to September.
The other shortcoming is that the article didn’t state whether any of the offspring developed rickets or other diseases. That would be interesting data to determine if we can see an actual correlation between low serum Vitamin D and clinical signs. However every month there is a new research article on Vitamin D and it seems that recommendations for pregnancy may be in the 1000-2000 IU/day range which is almost 5 times the current dosage in pre-natal vitamins. Oh yes I’ve also seen a brand of prenatal vitamins being recommended that contain ergocalciferol. Ergocalciferol is Vitamin D2, the inactive form of the vitamin and not very bioavailable. You want to make sure your neonate vitamin has cholecalciferol, Vitamin D3, the active form of the vitamin.
To read the entire article I’ve uploaded it for you and you can get it here: Maternal Vitamin D
In Health,
George Mandler
Licensed Acupuncturist & Nutritionist Dietitian
Acupuncture, Chinese Medicine, & Nutrition
Boston, Jamaica Plain, Brookline, Massachusetts