Dr. Barry Sears, founder and chairman of Zone Labs, has said the key to benefits from consumption of fish or fish oil supplements are due to the EPA, not the DHA.

“Expectant mothers have always been told that fish is brain food not only for the developing child, but for the mother as well,” said Dr. Sears. “New research data questions that ancient wisdom, or does it?”

According to Dr. Sears, one of the leading experts in omega 3 fatty acids, “To understand this seeming paradox requires a detailed knowledge of fish oils and omega 3 fatty acid metabolism that is not available to most medical journalists.”

Dr. Sears explained that there has been a growing body of knowledge that women who consume fish or fish oil supplements have less post-partum depression, and their children have improved cognitive development. However, fish and fish oil supplements always contain a mixture of EPA and DHA.

“Because the brain contains relatively low amounts of EPA compared to DHA, it has always been assumed that it was the DHA that gave rise to these benefits. In fact, an entire industry was built on the concept of supplementing infant formulas with DHA would improve the neurological health of both the mother and child. Of course, no one ever tested this hypothesis until now,” said Dr. Sears.

He noted, “The October issue of the Journal of the American Medical Association published an article looking at the dietary supplementation with a fish oil supplement exceptionally high in DHA and very low in EPA. Unfortunately, the results were the opposite of the prevailing thoughts. In fact, the researchers found no cognitive benefits for either the mother or child. This calls into question why we are supplementing infant formulas with DHA.”

Dr. Sears said, “The answer is that benefits of fish consumption or fish oil supplementation are due to the EPA, not the DHA.”

He added that both EPA and DHA get into the brain, but the EPA is rapidly oxidized, whereas the DHA is shunted into long-term storage. “This explains why there is little EPA found in the brain, leading to the misconception that it isn’t important in the brain. However, while the EPA is present in the brain, it can act as a powerful anti-inflammatory agent.”

Dr. Sears hypothesized, “It is this anti-inflammatory action that is responsible for the neurological benefits. This is confirmed by numerous studies in which DHA has little, if any benefits, in treating depression or attention deficit hyperactivity disorder, whereas fish oils rich in EPA do have remarkable benefits.

In his advice to expectant mothers, Dr. Sears said, “Eating fatty fish rich in EPA may not be the answer since those fish contain relatively high levels of pollutants, such as PCBs. On the other hand, fish oil supplements rich in EPA and with exceptional purity with regard to PCBs may be the answer.”