Omega 3 and Omega 6 are two categories of essential fatty acids (EFAs) required by the body from dietary sources. We can’t manufacture EFAs ourselves, so they need to be an essential part of our food intake. Essential fatty acids are found everywhere in the body – they form the outer membrane of every cell in the body; they help nerve function, brain function, heart health, and many other aspects of health.

Omega 3 is made up of different fatty acids – alpha linolenic acid (ALA), docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA). ALA is found in nuts and seeds, like flaxseed for example, but to use ALA, the body must break it down to EPA and DHA. EPA and DHA are found commonly in fish, but can also be found in lamb or beef, and eggs.

Omega 6 is made up of linoleic acid (LA) and is further broken down to gamma-linolenic acid (GLA) and arachidonic acid (AA). Omega 6 is found commonly in grains, nuts, seeds, vegetable oils, and all animal based foods that have been fed omega 6 sources.

Ideally, humans should eat Omega 6 and Omega 3 in a ratio of 4:1 (four omega-6’s for every 1 omega 3), with 1:1 being the optimal ratio mentioned by those who study longevity. Many on a modern western diet are eating well out of this ratio, with 12:1 omega 6 to omega 3 being consumed. This imbalance can lead to a wide range of signs of poor health for our bodies.

What do Omega-3 fatty acids do in the body?

Omega-3 is required at every stage of life from conception onwards, to enable us to achieve our learning potential and optimise behavioural development. Having adequate essential fatty acids through pregnancy is vital for healthy brain development of the baby. It is also just as important in an ageing brain, to support memory, brain health, and cognition.

Both EPA and DHA have supportive actions through the body, but these fatty acids do have slightly different functions:


Involved largely in inhibiting arachidonic acid which creates inflammation within cells, having adequate or high available levels of EPA in the blood is supportive of brain health, learning capabilities, normal healing from trauma, joint movement and flexibility, and healthy mood balance, all of which can be at risk when EPA is low.


DHA works to keep cell membranes fluid. DHA is an essential component of the nerves, allowing healthy communication pathways throughout the body but particularly in nerve rich areas like the eyes, and brain. Having adequate levels of DHA helps support heart and cholesterol health because it makes it difficult for LDL (the ‘bad’) cholesterol to settle in the arteries.

Getting the balance right

For a healthy balance of Omega 3 and Omega 6 EFAs through daily food intake, either the Mediterranean or Paleo diets are recommended, being rich in Omega 3 through both fish and plant sources. Having too much omega-6 in the diet is relatively easy if you eat a lot of processed foods, and too much omega 6 can create inflammation in the body.

Sources of Omega 3

Omega-3 fatty acids are found in many whole foods. The best sources of omega-3 are mackerel, salmon, cod, walnuts, sardines, pasture-raised beef and lamb, eggs, algae, flaxseed, hempseed, chia seeds, and green lipped mussel

Omega 3 Fish Oil vs plant based Omega 3

In recent studies, evidence has emerged that the plant based sources of Omega 3 (flax seed oil, for example) may be as important as fish oils in maintaining healthy heart function. This is because plant-derived Omega 3s contain high amounts of naturally occurring vitamin E which keep protect the fat from oxidation. Omega 3 from fish oil can contain much lower levels of Vitamin E, and so extra is added in the manufacturing process. However, plant derived Omega-3 only provides the fatty acids in the ALA form, which the body needs to break down into DHA and EPA using two different enzymes. If the diet is high in processed foods, or the body is genetically wired in a certain way, this conversion is difficult. For vegetarians or those who do not eat fish, there is an algae based Omega 3 which provides the EPA and DHA fatty acids.

Avoiding pollutants & supporting sustainability of fish resources

Mercury and other pollutants (including solvents, pesticides, PCBs, lead, chromium, cadmium, strontium, and arsenic) discharged into our oceans from industrial waste are contaminating fish populations at an alarming rate. High levels of these toxins are not as present in the tissues of smaller fish such as sardines, anchovies, or herring. Look for a product that has been tested to contain no mercury.

It is also important to consider the sustainability of the fishing practices used to harvest the fish oil. Make sure you buy from companies who prioritise the health of the environment alongside the health of their customers.

By the HealthPost Naturopaths