When I try to remember, I always forget. A.A.Milne, Winnie the Pooh

The brain of the foetus, and the baby for the first two years of life, is rapidly growing, with nerve cells dividing to form new cells, pathways and "organs", so the need for DHA is very high at this time.  There is scientific evidence that the conversion of plant type omega-3s, such as alpha-linolenic acid (ALA), poor at the best of times, is even less efficient in the immature brain.  Moreover, the supply of DHA to the baby at this critical time may be important for future brain function.

The following figure, taken from Helland's 2003 paper, is illustrative:

 

The four double columns are different subsets of mental ability tests.  The shaded columns are for children aged four whose mothers took cod liver oil in pregnancy and lactation and the non-shaded are for children of mothers who took corn oil during pregancy and lactation.  There is clearly a significantly better mental ability in the children of mothers who took cod liver oil supplements at that critical period of brain growth four years earlier. 

This makes it all the more important that the mother provides a good source of DHA to the foetus and the baby, the latter not only during breast feeding but also after weaning.  We don't recommend that pregnant or lactating mums take cod liver oil, because of the vitamin A content, but we do recommend they eat oily fish once or twice a week.  If you are a mother who cannot abide oily fish, or a healthcare professional wishing to help such a mother, the obvious answer is to look to a fish oil supplement that does not contain vitamin A.  I have given additional advice on this in my book, The Brain Food Diet.  This evidence is now widely accepted in scientific circles and from 2000 onwards formula milk manufacturers in the US and Western Europe have included DHA in bottled milk.

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