Vitamin D Newsletter

Newsletter

Cod Liver Oil During Pregnancy

Joanne from Pennsylvania writes:

Dr. Cannell: I took cod liver oil during my pregnancy and everything went fine except a little high blood pressure but that would have been worse except for the omega-3 oils in cod liver oil. Why don't you read about cod liver oil on the Weston Price Foundation's website. 

Dr. Cannell replies:

 In one study, women who took cod liver oil during pregnancy were 5 times more likely to develop hypertension during their pregnancy.

In one study, women who took cod liver oil during pregnancy were 5 times more likely to develop hypertension during their pregnancy. The authors attempted to control for intakes of vitamins A and D but the cod liver oil the women took contained about 10,000 IU of vitamin A and only 800 IU of vitamin D. By the way, the paper reports that the vitamin A content of Icelandic cod liver oil was reduced five fold in 2006, from 8,000 to 1,200 IU per 10 cc, mainly due to the literature showing vitamin A causes birth defects.

Jill from Oregon writes:

Dr. Cannell: I am six months pregnant and I took cod liver oil up until now. Will my baby be deformed?

Dr. Cannell replies:

While I don't know how much cod liver oil you took, or the brand, the chances are overwhelming that your baby will be just fine. Three well-conducted case controlled trials showed excessive vitamin A leads to birth defects. The first study, Teratogenicity of high vitamin A intake (PDF format) you can download for free, thanks to the NEJM. You can get the other two references from the downloaded paper if you are interested. But don't be alarmed Jill, the vast majority of women taking vitamin A had normal babies.
Also, when people tell me they take cod liver oil, I have no way of knowing what they actually taking—in terms of vitamin A and vitamin D—as different cod liver oil brands have such widely varying amounts of both vitamins.

Page last edited: 22 May 2011