There has been considerable confusion in the minds of many pregnant women, or those trying to conceive, around the subject of eating omega 3 rich fish or supplementing with fish oils. One the one hand, these essential fatty acids are crucial to the development of unborn children. On the other, there is the real risk of mercury contamination. Underlying this controversy, is the sad fact that as many as 85% of expecting mothers are deficient in these important fats. This article will discuss some of the benefits and dangers of fish oils, as well as looking at what scientists recommend in light of it all.
The fish oils under review are rich in the omega 3 fatty acids, which are essential fatty acids that the body cannot make itself. They must be derived from food, fortified food, or supplements. Generally, it is oily fish like mackerel, sardines, herring and salmon that are the source of these.
Yet, in a survey conducted by Women’s Health Research, based in Washington, only 41% of mothers and expecting mothers were aware of the health benefits of omega 3 fatty acids during and after pregnancy. With such statistics, it is not hard to see why so many women are deficient in essential fatty acids during pregnancy. In fact, it is believed that only 2% of pregnant women were getting the right amounts of EPA and DHA – either through diet or supplements.
EPA stands for eicosapentaenoic acid, and DHA is docosahexaaenoic acid. Both are the active constituents of fish oil, contributing to the structure and function of a healthy brain and nervous system.
Without these healthy fats, a baby’s brain and nervous system will not grow optimally. DHA is recognized as being so important that it is now added to some infant formulas, as babies need a lot in the first 2 years of life. DHA contributes to the actual structure of the growing brain, and constitutes about 8% of its’ weight!
EPA, on the other hand, is particularly important for the functioning of the brain and nervous system. If a pregnant woman is not getting enough EPA and DHA in her own diet, she can lose as much as 3% of her own brain mass in the last 3 months of pregnancy, as the EPA and DHA stored in her own brain is transferred to her baby. Is this why pregnant women complain of feeling forgetful so much!
An interesting study carried out at the University Of Western Australia provides some clues of the role of fish oils in a child’s fetal development. 83 women completed the study, approximately half of whom were given 4 grams of fish oil from 20 weeks until birth, and the remainder given olive oil supplements. The children’s development was measured when they were two and a half years old, and there was found to be an improvement in comprehension, average phrase length, and vocabulary in those whose mothers had taken fish oil when they were pregnant. The researchers reported that overall language skills were the same for each group. They did find that when babies had higher levels of omega 3 fatty acids in their cord blood, there was an improvement in hand and eye coordination. Levels of vegetable oils had no impact on hand-eye coordination.
Whilst it can be seen that fish oils are highly beneficial for pregnant women, the potential problem women face is contamination of the oil with mercury, PCB’s and dioxins. Mercury contamination can increase the risk of premature births, although the actual incidence of mercury contamination and premature birth associated with fish consumption is very low. One study conducted at Harvard and Michigan State Universities, that did find a link, reported only 4% of the women in the study actually gave birth prematurely.
These facts, combined with inconsistencies in studies that reported links between fetal development and mercury exposure, have led scientists to continue recommending pregnant women eat oily fish or take fish oil supplements. The benefits in fetal development, from brain and nervous system development, to coordination and improved vocabulary and comprehension as toddlers, all point to the benefits outweighing the risks. Indeed, one scientist involved in a review of various studies, said he was actually surprised by how little harm was reported. The risks to pregnant women are even further reduced if they source their fish oil supplements carefully.