We've all heard about the health benefits of omega fatty acids, with omega-3 and omega-6 receiving most of the attention. But the matter isn't quite this simple: there are many different forms of omega fatty acids.
Omega-3 and omega-6 refer to the two different families of essential fatty acids. Specific fatty acids within the different families, so-called DHA (docosahexaenoic acid) and EPA (eicosapentanoic acid), are crucial to health. These fatty acids are fairly scarce within the modern-day diet and special effort needs to be made to ensure an adequate intake.
Anne Till, registered dietician, says the importance of DHA for optimal infant development shouldn't be overlooked. DHA should be considered an essential nutrient for women who are pregnant, breastfeeding or planning to fall pregnant.
"Although DHA is essential, our bodies don't manufacture this fatty acid," she says. "It's therefore necessary to make sure we get enough DHA through diet, supplementation, or both."
Sixty percent of the infant brain is made up of essential fatty acids, half of which are DHA. The other half is made up of arachidonic acid (AA). AA, part of the omega-6 family of fatty acids, tends to be abundantly available in the western diet and supplementation with this fatty acid isn't required. In contrast, the availability of DHA is poor.
Get the balance right
It's currently estimated that the omega-6 to omega-3 ratio in the western diet is 16:1. We should be all aim to achieve a more beneficial ratio of 3:1 or 2:1. This is particularly important if you're pregnant or breastfeeding. Research shows that a mother's DHA intake during pregnancy and breastfeeding enhances the development of her baby's eyesight, nervous system and brain, while at the same time helping to reduce postpartum depression.
DHA is found in cold-water fatty fish such as salmon, trout, sardines and pilchards. The parent fatty acid, alpha-linolenic acid (ALA), is found in flax seed and green leafy vegetables. However, our bodies are not efficient in converting ALA to the desirable end-stage metabolite DHA. In fact, it's currently estimated that only between 1-5% of ALA is efficiently converted to DHA. So, consuming a direct source of DHA such as fatty fish is definitely more desirable.
All things considered
But there are ecological concerns regarding over-fishing and risks for pregnant women to consider, as some fish such as tuna, shark, marlin, tile fish, king mackerel and sword fish can be contaminated with mercury, polychlorinated biphenyls (PCBs) and dioxins. Mercury is associated with damage to the development of the infant's nervous system.
Taking all these factors into consideration, Anne believes that the simplest solution is to take DHA in supplement form. "It's critical to ensure that whichever supplement you choose contains DHA and not just omega-3, and to make sure that you get the right benefits for yourself and your baby," she says. " For example, you can take flax oil that contains ALA for as long as you like, but it won't give your body the DHA it needs."
Anne recommends checking the labels of supplements. The label should state that the product contains DHA and not just the parent fatty acid ALA or unspecified omega-3. If you're pregnant, you should take an estimated 200mg of DHA daily. Everyone else will get the right level of this essential fatty acid by taking approximately 140mg a day.
"If you're unsure which supplement is right for your specific needs, it's best to seek professional advice," she furthermore advises. "From a family-planning perspective, a supplement that provides the required vitamins, minerals and DHA is ideal."
If you're planning to conceive, it's definitely also worth focusing on your intake of fatty acids."If you are planning ahead, there are also significant benefits to be derived from following a balanced diet and taking a supplement containing folic acid and DHA as early as six months before conception, Anne concludes.
(Redline, November 2009)
Read more: Why your brain needs fish