I can’t think of a more vulnerable person than a pregnant woman. She is both responsible for herself and for another human growing inside of her. It is an incredible duty.
In a sad finding (bound for future woe), a group in England, led by Dr. Maryam Parisaei, measured vitamin D levels of 207 women on their first obstetric visit. Fifty-six percent had levels less than 10 ng/ml and an additional 32% had levels less than 20 ng/ml. In all, 88% were severely vitamin D deficient while their babies’ brains were in the process of developing.
It was not just the dark-skinned mothers who were deficient; many light-skinned mothers also had low levels. In the words of Dr. Parisaei,
“This was an extremely unexpected finding as it highlights that this is a greater problem than described previously. We were surprised to find that 34% of the women who were deficient would have previously been defined as “low” risk for vitamin D deficiency. This includes ‘white’ women, who were born and brought up in Britain.”
The authors went on to quote a study showing that treatment of pregnant women with a 200,000 IU “Stauss” dose followed by 800 IU/day (more than the 600 IU in standard prenatal vitamins in the USA) left only 30% of the women and only 8% of the babies with levels above 20 ng/ml. The authors concluded,
“…despite the introduction of antenatal guideline (prenatal vitamins), there remains a pressing need to identify both the right dose and timing of vitamin D supplementation. This study highlights the need to urgently review the current recommendation as higher doses and longer duration of prenatal vitamins may be required.”
It is good to see another researcher join our call. We need more.
The only factual mistake I could find was the statement, “Breast milk has little vitamin D even when maternal levels are adequate.” False, as Professor Bruce Hollis has shown, 6,000 IU/day for breast-feeding moms produces breast milk rich in vitamin D. As I have written, the blood level required for breast milk to become rich in vitamin D is by far the most meaningful biomarker of vitamin D adequacy that we have as a species.