"Should Vegan Women Supplement with DHA During Pregnancy?"
A systematic review of randomized controlled trials
of DHA supplementation of pregnant and breast-feeding women
failed to find any clear and consistent short or long-term benefit
for psychomotor, mental, visual or physical development.
Maybe DHA supplementation during pregnancy has no effect
because the body isn't stupid and protects the growth of the baby's
brain by drawing off of maternal stores of DHA, upregulating maternal
DHA synthesis, and preferentially shuttling it to the fetus.
But what if moms don't start out with large maternal stores?
In other words, maybe DHA failed to help women
who were already getting enough, but maybe women
with very low intakes would benefit from DHA supplementation.
Well, first it's interesting to note that even by 1978
researchers were suggesting plant-based diets as the diet of choice
in the treatment of our number one killer.
But babies breastfed by vegan moms
have significantly less DHA in their bloodstream presumably
because the moms had significantly less DHA in their breast milk.
The question is whether these differences are of any consequence?
The growth and development of vegan and vegetarian children are normal,
as long as they're getting their B12.
No evidence that neural or intellectual functions are impaired.
In fact the two studies we have on vegetarian kids
showed that they had higher IQ's, though that may have been
because their parents tended to be better educated.
But even though the kids seemed fine, that doesn't rule out the possibility
that there may be some subtle differences
in visual or neural functioning.
It would be interesting to compare the function of babies getting
vegan breast milk levels versus general population levels.
You can see vegans had 14, vegetarians 30, omnivores 37.
This study compared zero to 32, 64, and 96,
and 32 worked better than zero, but more than 32 didn't add anything.
This could explain why the general population at 37 doesn't benefit
from additional DHA supplementation.
But what about down at 14?
Most studies down at that level showed no advantage over zero,
though one study found a benefit supplementing at as low as 5,
but that doesn't help us.
Now just because babies breastfed by vegan moms
have significantly lower DHA levels in the blood
doesn't necessarily mean they have lower levels in their brain,
which is where it counts.
What we need is a randomized, controlled trial in non-fish eaters
of DHA supplementation. Until then, it's going to remain uncertain.
So what should pregnant and breastfeeding women
who avoid fish do in the meanwhile?
Low intakes of DHA doesn't necessarily equate
with fetal DHA inadequacy,
but this new data suggests that some infants may not be getting enough
and could benefit from their moms supplementing.
And so I recommend pregnant and breastfeeding women
on plant-based diets do follow the consensus guidelines
to get about 200mg of preformed DHA from an uncontaminated source
like algae oil, which is probably the best combination for all women
given the state of our world, to minimize exposure
to toxic pollutants such as dioxins, PCBs, and mercury.