Essential fatty acids began gaining attention when researchers were studying the health of Inuit and Japanese populations. They noted that the mortality rate from cardiovascular disease in these populations was much lower than that observed among North Americans, even though their diet is much higher in fat than ours. However, fats found in fish, seals and whales (in other words, foods consumed mainly by the Japanese and Inuit) are very rich in essential fatty acids, unlike those that make up our diet.
These fatty acids are called essential because the human body cannot make them on its own; we must therefore get them through our diet or supplements. Essential fatty acids contribute overall to the proper functioning of several organ systems. They are divided into three categories: omega-3, omega-6 and omega-9 fatty acids. The body produces all the omega-9 fatty acids it needs, but omega-3 and omega-6 fatty acids must come from the diet.
OMEGA-3 FATTY ACIDS
Omega-3 fatty acids are the most beneficial to the human body. They are involved in many processes required to maintain the integrity of several systems. Among other things, they help control blood pressure, maintain the elasticity of the blood vessel walls, and help build and repair cell membranes. They also contribute to the functions of the nervous system and the regulation of inflammatory and allergic reactions.
There are three essential fatty acids in the omega-3 category: alpha-linolenic acid (ALA), eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA).
Alpha-linolenic acid (ALA) ALA is a precursor to the other omega-3 fatty acids, EPA and DHA. It is mainly found in vegetable sources, such as flax and hemp seeds and their oil, as well as canola and soybean oil. According to the Health Canada recommendations, the minimum daily intake of ALA should be 1.1 gram for women and 1.6 grams for men. This would represent, for example, two teaspoons of ground flax seeds, a quarter cup of walnuts or a tablespoon of canola oil. Omega-3-enriched eggs, incidentally, provide more than a quarter of the daily recommended intake of omega-3 (as ALA).
Eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) EPA and DHA play a role in cardiovascular health, inflammatory process regulation, brain and retinal development, and sperm formation in men. The body can produce these two fatty acids using ALA, but we still get them mainly from the flesh of fatty fish such as tuna, salmon, herring or mackerel. The recommended intake of EPA and DHA is 0.3 to 0.5 grams per day if paired with a sufficient ALA consumption, or 1.3 grams of marine-source omega-3 per day. For example, this would be the equivalent of 70 grams of fresh Atlantic salmon or 120 grams of canned tuna. You can also take fish-oil supplements, which are sold in pharmacies. Speak to your pharmacist for more information on these products.
OMEGA-6 FATTY ACIDS
Omega-6 fatty acids also offer many health benefits, but when eaten in excess, they can predispose to certain inflammatory diseases, such as asthma, arthritis and eczema. These fatty acids nevertheless play an important role in maintaining nervous system and immune functions, as well as in regulating inflammatory and allergic reactions. There are many types of omega-6 fatty acids and they are plentiful in our diet, for example in corn, soybean and sunflower oils, as well as in egg yolks and animal fats. It is not usually necessary to take omega-6 supplements, since there is often an excess of this fatty acid in the North-American diet.
A DELICATE BALANCE
While omega-6 fatty acids are beneficial to our health, consuming too much of them can hinder the work performed by the omega-3s. In order to reap maximum benefits from both categories of fatty acids, the omega-6/omega-3 intake ratio should be 1-4 to 1. However, it is estimated that the ratio is around 10-30 to 1 in the typical Western diet, which means that our dietary sources of omega-3 are barely harnessed due to our excessive omega-6 intake. Some experts suggest that simply restoring this balance in our diet could single-handedly and significantly reduce the rate of cardiovascular and inflammatory diseases in North America.
Making small changes to your diet to increase your intake of omega-3 fatty acids can have a real impact on your global health. Take a look today!