ESSENTIAL FATTY ACIDS (EFA)

As the name tells us, these fats are essential to our well-being. Essential, in this case, actually means that our bodies are not able to produce them on their own and therefore we must get these nutrients in our diet. As vegans, we need to be conscious about getting enough essential fatty acids (or EFA) and that we get them in the right ratio.

There are two EFAs for humans, both polyunsaturated fatty acids: linoleic acid and alpha-linolenic acid. Linoleic acid is part of the omega-6 family and is abundantly available in a vegan diet. Common sources are vegetables, fruits, nuts, grains and seeds. Oils made from safflower, sunflower, soya, evening primrose, pumpkin and wheatgerm also have high linoleic acid content. Alpha-linolenic acid, from the omega-3 family, is somewhat harder to come by because it is often removed in processing due to its tendency to turn rancid quickly. Vegan sources include flaxseeds, hempseed oil, spirulina, green leafy vegetables, mustard seeds, pumpkin seeds, soya beans and walnuts^[1] .

Three other important polyunsaturated fatty acids are arachidonic acid (AA), eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). These can either be consumed directly from food or they can be converted from the parent fatty acids, linoleic acid and alpha-linolenic acid. Consuming these PUFAs through food presents a challenge for vegans because AA is found in animal flesh and dairy products and EPA and DHA are found in fish and microalgae. Of these food sources, microalgae is the only vegan source and it is difficult to consume sufficient amounts in a regular diet. For this reason, our bodies can best access AA, EPA and DHA through conversion of linoleic acid and alpha-linolenic acid or through vegan supplements. There is one further complication … high intake of linoleic acid, typical of vegan diets, may suppress the body's ability to convert alpha-linolenic acid to DHA. This means that we need to be concerned about the ratio of omega-6 to omega-3.

How much is enough?

In answering this question, we need to consider, not only quantity, but also ratio. Some experts advise that one should consume a minimum of 3% of energy from omega-6 fatty acids and 0.5% from omega-3 fatty acids. This would mean that if you consume 2000 calories a day, 60 of those calories should come from linoleic acid (6.7 g) and 20 from alpha-linolenic acid (2.2 g).

Because linoleic acid is so plentiful, especially in vegan diets, it is easy to ensure those 6.7 grams. Achieving a healthy balance with alpha-linolenic acid, however, takes some planning. Most of the recommended ratios vary from 5:1 (omega-6:omega-3) to 10:1. Some, however, go as balanced as 1:1. We gain more clarity when we compare this range of ratios with the average North America intake which exhibits a ratio between 14:1 and 20:1, with some studies indicating higher ratios in vegetarian populations compared to omnivorous populations^[2] . The obvious discrepancy points to the fact that most people need to pay closer attention to their EFA balance.

Why do I need EFA?

EFAs aid in the formation of healthy cell membranes, the development and maintenance of the brain and nervous system, and the production of hormone-like substances called eicosanoids (thromboxanes, leukotrienes, prostaglandins). These chemicals regulate numerous body functions including blood pressure, blood viscosity, vasoconstriction, immune and inflammatory responses. It is believed that correct levels and balance of EFAs plays a critical role in the prevention and treatment of chronic diseases including coronary artery disease, hypertension, type II diabetes, arthritis and other immune/inflammatory disorders, as well as cancer^[3] .

Tips for getting them

Limit saturated fats and trans fatty acids intake. These fats can potentially interfere with the conversion of alpha-linolenic acid to DHA. For vegans with a healthy diet, limiting these fats should not be too difficult because the primary sources of saturated fats are animal flesh, dairy products and eggs. Avoiding tropical oils, other than coconut oil, is important. Consuming minimal processed foods, snack foods, fried foods and hydrogenated oils, means low trans fatty acid intake.

Make monounsaturated fats the principal fat in the diet. Of the 15 – 30% recommended fat intake in your diet, the majority should be monounsaturated fats. Not only do these fats have neutral or positive health affects, they also help to minimize the intake level of saturated fats, trans fatty acids and omega-6 fatty acids. Olive oil and/or non-GMO canola oil are good monounsaturated oils to use. Good food sources are avocados, olives, hazelnuts, pistachios, almonds, macadamia nuts, peanuts and pecans.

Limit the intake of omega-6 fatty acids. In order to maintain a healthy omega balance, minimize linoleic acid levels by choosing oils which do not contain omega-6. Oils to avoid include corn oil, sunflower oil, safflower oil, and cottonseed oil as well as any products made with these oils. Although soybean oil and walnut oil are also high in omega-6 fatty acids, their omega-6 content is partially counterbalanced by an omega-3 content of 5-8%^[4] .

Find strong sources of omega-3 fatty acids. Flaxseed oil is an excellent source with 57% omega-3 and only 17% omega-6. Using ground flaxseeds in your cooking will also provide you will lots of omega-3. Green leafy vegetables are the only other food source where omega-3 is proportionately higher than omega-6. Canola oil (make sure it’s non-GMO), walnut oil (and of course whole walnuts), and soy oil also offer some omega-3 though they also have high omega-6 content^[5] .

Footnotes