Within the realm of nutritional medicine, the role of essential fatty acids in human health is of great interest to me. I have been studying fats and essential fatty acids in particular, for a number of years. I am pleased to say that some of my published research in this area has received the attention of some of the world’s leading experts in the field. In addition, I have received scores of e-mails and letters from those who have successfully used essential fatty acids in various conditions, particularly chronic fatigue and mental health disorders as a result of some research that I have been involved with.

Essential fatty acids are fats that we cannot make – we must take them in from the diet – hence the name essential. These fats play critical roles throughout the body – from our immune system, to our brain, from our intestinal cells to our skin cells, essential fatty acids control many aspects of both structure and function.

There are 2 major classes of essential fatty acids – omega-6 and omega-3. Over the last century, humans have seen a major relative decline in the amount of omega-3 present in the diet, while omega-6 content has risen up dramatically relative to omega-6. While the overall intake of fat has declined in the last 30 years in North America, omega-6 fats have found their way into our food supply at an excessive rate. Interestingly, the fear of fat instilled in us by dietetic organizations and government recommendations has done little to curb obesity and chronic disease rates.

Genetically, humans have been accustomed to an omega-6 to omega-3 ratio of close to 1:1, a far cry from the current ratio which is at least 10 parts, and up to 20 parts omega-6 for every one omega-3. In 1999 an international panel of 30 of the world’s leading fat experts convened in Washington DC and recommended that the dietary omega-6 to omega-3 intake ratio should be close to 1:1. They published this recommendation in the Journal of the American College of Nutrition (1999Oct;18(5):487-9).

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When we mess around with the dietary essential fatty acid ratios in such a short period of time, as we have done over the last half-century, fallout should be expected. Indeed, in recent years scientists have shown that the extreme changes in essential fatty acid ratios do influence structure and function of human cells. Most notably, the over-consumption of omega-6-rich oils such as corn, safflower, sunflower and soybean oils have the potential to promote inflammation and oxidative stress. Soybean oil has a little omega-3 content, however it is very high in linoleic acid omega-6 which can promote inflammation. The intake of soybean and other omega-6-rich oils is enormous in North America relative to Japan where rates of cardiovascular disease and many chronic conditions are much lower.

Omega-3 fatty acids, on the other hand, have been shown to be anti-inflammatory in the body. They have also been shown to lower oxidative stress, and to be beneficial in a wide variety of medical conditions. Omega-3 fatty acids are found in fish, seafood, flaxseeds, walnuts, canola oil, free-range meats and to a limited degree in dark green leafy vegetables.

Sadly, North American intake of two key omega-3 fatty acids, docosahexaenoic acid (DHA), and eicosapentaenoic acid (EPA) is a paltry (combined) 130mg per day. Consider that the aforementioned international panel of fat experts recommended a minimum of 650mg of EPA/DHA per day. These 2 key omega-3 fatty acids, EPA and DHA, are found pre-formed in fish and seafood, while other omega-3 sources such as flax contain the parent omega-3 called alpha-linolenic acid (ALA). The ALA must be converted in the liver into heart and brain friendly EPA and DHA. This conversion is limited in humans - only a small percentage will get converted into EPA and DHA which is why many experts recommend fish oil as a means to pump up the EPA and DHA status, and it is also the reason why the vast, vast majority of omega-3 fatty acid clinical research has been conducted using fish oil.

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As you are probably aware, both inflammation and oxidative stress (free radical generation) are at the hub of most of our chronic health conditions – from Alzheimer’s disease to schizophrenia, from cardiovascular disease to rheumatoid arthritis, from diabetes to obesity, inflammation and oxidative stress are common threads. Even mental disorders such as depression and anxiety are associated with excess oxidative stress and the generation of inflammatory chemicals.

Keeping in mind that the brain is 60% fat, and that brain cells are dependent upon dietary fats for structure and function, it may not surprise you that low omega-3 fatty acids have been connected to so many brain-related conditions. How an omega-3 fatty acid deficiency (or relative excess of omega-6) may present itself in an individual likely comes down to genetic susceptibilities.

Some confusion arises with essential fatty acids because there is a ‘good’ oil which is labeled as part of the omega-6 family. It is called gamma-linolenic acid (GLA). This particular fat is derived from 3 primary sources – evening primrose oil, blackcurrant seed oil and borage oil. Of the three, it is the borage oil which is most abundant in GLA. It is important to stress that the aforementioned linoleic acid-rich oils (corn, safflower, sunflower, soybean) do not contain GLA. This is an important distinction because GLA, unlike linoleic acid, has been shown to have anti-inflammatory properties. Due to its anti-inflammatory properties, GLA may be important in the prevention and treatment of arthritis and various skin conditions. In commercial essential fatty acid products, borage, blackcurrant or primrose oils are usually included as the “omega-6”. Supplementation with commercial products containing linoleic acid oils in the absence of GLA should be avoided – we get more than enough from the diet.

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Brain-Related conditions with connections to low omega-3 and /or omega-3 include:

Alzheimer’s disease/Dementia
Attention deficit hyperactivity disorder (ADHD)
Autism
Bed wetting (enuresis)
Bipolar disorder
Borderline personality disorder
Childhood I.Q./Learning
Chronic fatigue syndrome
Depression
Dyspraxia
Dyslexia
Epilepsy
Fibromyalgia
Huntington’s disease
Migraine headaches
Multiple sclerosis
Parkinson’s disease
Post-partum depression
Seasonal affective disorder
Social phobia
Schizophrenia

Its not only brain-related conditions where omega-3 fatty acids have been shown to be low - there are a host of other conditions where omega-3 levels (relative to omega-6) are low and/or interventions with omega-3 fatty acids have been shown to be helpful.

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When scientists observe one dietary factor related to so many medical conditions which affect many of the body’s systems, it is a huge red flag that something is just not right in the modern diet – something is missing.

Various Sources of EPA and DHA

Table 2. Omega-6 and Omega-3 Content (%) of Dietary Oils

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 Vegetable oil supply in Kg per person in 1961, 1970 and 2002

Per Capita Soybean Oil Supply Kg/Person in Japan and the USA

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