Omega this, omega that. Fish oil, flax seed oil, DHA, EPA… The buzz around essential fatty acids has reached levels that might lead one to think the fountain of youth had been discovered. Well, almost…

At the very least, unless you’ve been living in a cave, you’ll know that essential fatty acids (EFAs) are “good” for you. But what are they, really? And just why have they found such popularity in today’s health-obsessed culture?

Fatty Acids

Fatty acids are simply components of fats. What makes them so important, though, is that they are incorporated into the membranes of every cell in the body and so have a staggering array of functions.

The Omega Families

Fatty acids are grouped into families. And some of the fatty acids in two of the families are “essential”, that is, they cannot be manufactured or synthesized by the body and must be obtained through diet.

There are three omega families: omega-3, omega-6 and omega-9.

For the technically minded, the nomenclature refers to the position of the first double bond in a series of carbon-carbon bonds, counting from the terminal end of the molecule. In an omega-3 molecule, then, the first double bond exists at the third carbon-carbon bond.

Of the three families only omega-3 and omega-6 contain essential fatty acids. While the omega-9 family is necessary for health, it is not “essential” as the healthy human body can manufacture this group of EFAs itself.

Let’s Make it Simple

Two families. Two acids.

The fatty acid that is essential to us from this family is called alpha-linolenic acid (ALA).

The essential fatty acid in this family is linoleic acid (LA).

Where it Gets a Little More Complicated

As any visitor to a health food shop knows, though, there’s a whole lot more on those fish oil and flax seed labels than just ALA and LA. So what’s going on?

Well, in layman’s terms, alpha-linolenic and linoleic acids are just raw materials that the body uses in the manufacture of other fatty acids. More technically, ALA and LA are short chain polyunsaturated fatty acids that the body converts to long chain polyunsaturated fatty acids.

What it Breaks Down To

Alpha-linolenic acid is used by the body to produce:

  • Eicosapentaenoic acid (EPA)
  • Docosahexaenoic acid (DHA)

If you’ve ever bought fish oil you’ll have seen references to EPA and DHA in the nutritional information on the product wrapper.

Linoleic Acid is used by the body to produce:

  • Gamma-linolenic acid (GLA)
  • Dihomo-gamma-linolinic acid (DGLA)
  • Arachidonic acid (AA)

You’re likely to have seen GLA, at least, on the sides of flax seed oil bottles.

But hang on, isn’t everyone saying that EPA, DHA and GLA are essential fatty acids? Isn’t that why I’m swallowing handfuls of fish oil capsules and guzzling flax seed oil?

While it’s true that these fatty acids are very definitely essential for our bodies to function, they are not technically essential because, given the right resources (alpha-linolenic acid and linoleic acid) our bodies can manufacture them.

There is a caveat to this, though. Research indicates that the conversion of alpha-linolenic into EPA and DHA does not always happen efficiently, and consequently levels of these essential fatty acids may be insufficient. If this is the case, then EPA and DHA become “conditionally” essential and must be found directly in the diet.

What Fatty Acids Do

Omega-3 fatty acids aid in circulation, the formation of cell walls, oxygen uptake and the production prostaglandins which regulate heart rate, blood pressure, fertility and inflammation.

Deficiencies in them have been linked to, among other things, poor vision, diminished immune function, increased LDL levels (“bad” cholesterol), learning disorders and increased blood clot formation and heart disease.

Omega-6 fatty acids are less trumpeted for their benefits but are still essential to health. Some fatty acids within this family are associated with lower levels of heart disease and have been found to suppress the production of adhesion molecules in blood vessels. They are also beneficial in diabetic neuropathy, rheumatoid arthritis and PMS.

Essential Sources

Good sources of Omega-3 fatty acids are: flax seed oil, walnuts, Brazil nuts, pumpkin seeds, sesame seeds, avocados, soybean oil, wheat germ oil, canola oil, oily cold-water fish (salmon, trout, sardines, tuna, anchovies etc.)

Good sources of omega-6 fatty acids are: flax seed oil, grape seed oil, pumpkin seeds, raw sunflower seeds, olives and olive oil, evening primrose oil, soybean oil, safflower oil, sunflower oil.

Essential fatty acids are damaged by heat, so, if health is a concern, try where possible to avoid cooked or heated forms of the foods listed above. Flax seed oil, for instance, should never be used for cooking. When eating nuts, go for raw over roasted.

Choose your oils carefully. Highly refined oils may have very little of the healthy EFAs left in them.

A Healthy Balance

When choosing omega foods or supplements it is important to consider the ratio of omega-6 to omega-3. Generally a ratio of between 1:1 and 4:1 is recommended. In the West we tend to consume far too much omega-6 as it is so prevalent in our foods (think about all that vegetable oil we cook with) and supplementation is unlikely to be necessary. In America the average diet has an omega-6/omega-3 ratio of 20:1!

Omega-3 is a different story – we tend to consume too little of the foods rich in these essential fatty acids and for some people supplementation may be indicated . The New Zealand Ministry of Health recommends an omega-3 intake for women of 430mg per day, and 610mg per day for men.

A Word on Fish Oil

Fish oil is one of the easiest and most convenient ways to supplement your omega-3 intake. EPA and DHA are directly available in this oil so the body is not forced to synthesize them from alpha-linolenic acid. However, rancid fish oil may not only fail to provide the expected nutrients, it may actually be harmful to the body.

In New Zealand, unlike Australia, the Dietary Supplements Regulations do not provide for the auditing of manufacturers’ processes. It is impossible to tell, then, from the information provided on the label, if the fish oil you’re buying is rancid or not. Generally, the older the oil, the greater the chance it’ll be rancid. To safeguard yourself, don’t choose a fish oil that is close to its expiry date. Similarly, as heat and light damage oil, don’t buy fish oil supplements that have been stored under hot, bright lights.

An Indispensible Addition

Unlike many of the health fads of the last few decades, the volume of positive research around essential fatty acids has meant that they are now established as an indispensable part of a healthy diet.

So, choose your foods and supplements carefully, avoid heating EFA-rich foods where possible, look for unrefined versions of EFA-rich oils, and pay attention to the omega-3/omega-6 balance. The fountain of youth? Maybe not. But the evidence certainly tends to suggest essential fatty acids will help you live a healthier life.

Learn a little more about fish oil here:

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