Having recently delivered a baby, I was surprised to see the latest article published in the Journal of The American Medical Association that fish oil supplementation rich in DHA has no impact on postpartum depression or cognitive and language development in early childhood.
The study looked at approximately 2,400 Australian women who began supplementation at around 21 weeks gestation through to the birth of their children (1). Individuals were randomized into one of two groups, one getting a fish oil supplement exceptionally rich in DHA (800mg DHA and 100mg EPA) and the other vegetable oil. It has been know for years that fish oils containing both EPA and DHA have dramatic benefits for fetal outcome. However, since there is little EPA in the brain, it was assumed in the past that it was only DHA that contributed to all of these benefits. However, recent studies have demonstrated that EPA rapidly gets into the brain and is rapidly oxidized, but DHA is not (2).
Lack of awareness has led to the mistaken belief that DHA is the only omega-3 fatty acid attributed to optimal brain functioning. Needless to say, companies that market DHA-rich products work very hard to continue to foster this misconception. This explains why the clinical trials that have used only DHA to treat depression or other conditions such as ADHD have been found it to be wanting. This is because DHA is a structural omega-3 fatty acid, not an anti-inflammatory one like EPA.
As long as adequate EPA is constantly in the blood, there will be enough EPA in the brain to address any neurological problems for both the mother and the fetus. That’s why this published study with only 100 mg of EPA was providing essentially a placebo level of this critical omega-3 fatty acid (3).
Although I myself am only a data point of one, I took the same dosage of DHA described above (800mg) during my pregnancy, however, it was coupled with 1600mg EPA. I can’t help but think that it may have been the combination of EPA/DHA that helped me avoid postpartum depression.