A nyone who stays abreast of nutritional science knows that perhaps the topic of greatest discussion currently is the need for more omega-3 fatty acids in the diets of most North Americans. The question is, “How is this best accomplished?” While there is, of course, no “magic bullet” single answer, there are new breakthroughs in functional foods and dietary supplements that can be part of the solution. WHAT ARE THE MAJOR OMEGA-3 FATS? Alpha-linolenic acid (ALA) is a plant source of short chain omega-3 essential fatty acid (EFA). The all-important long chain omega-3 fats are eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). EPA is not technically “essential” because our bodies make EPA from ALA, though it widely rates.1 However, DHA conversion from ALA is so poor in many persons that some authorities think it should be classifi ed as “conditionally essential.” 2 Alpha-linolenic acid is found mainly in fl ax seeds, walnuts and in plant oils like fl ax, canola and soybean oils. Flax seeds and fl ax oil are the richest sources of ALA in the North American diet.3 EPA and DHA are found mainly in fatty fi sh like herring, salmon, mackerel and bluefi n tuna and the fi sh oil supplements made from them. Marine algae, the bases of the oceanic food chain, are rich sources of DHA, but contain little EPA. At the present time, there is no Recommended Dietary Allowance (RDA) for EFAs in the U.S. However, the National Academy of Sciences’ Institute of Medicine (IOM) recommends 1.6g/day of ALA for men and 1.1g/day for women.4 The American Heart Association (AHA) and the Heart and Stroke Foundation in Canada recommend that fatty fi sh be consumed twice a week.5 THE IMPORTANCE OF THE OMEGA 6-3 RATIO Omega-6 fatty acids, specifi cally linoleic acid (LA) and arachidonic acid (AA), are also essential. However, in many ways they act opposite to the anti-infl ammatory and “blood thinning” actions of the omega-3 fatty acids. Specifi cally, they tend to promote infl ammation and clotting. They also compete with enzymes that help short chain ALA be converted to long chain EPA and DHA.6,7 Therefore, the consensus recommendation is to eat more “anti-infl ammatory” omega-3 fats and fewer pro-infl ammatory omega-6 fats and saturated fats.8 DO ALL OMEGA-3 FATS HAVE THE SAME HEALTH BENEFITS? Omega-3 fats are alike in some ways and different in others. Alpha-linolenic acid, EPA and DHA all act in support of keeping cell membranes fl exible and elastic, and block the actions of some compounds that cause infl ammation and clotting.9 Chronic diseases like heart disease, diabetes, cancer and arthritis are marked by infl ammation. Therefore, all omega-3 fats help reduce chronic disease risk by blocking infl ammation.10,11 Still, it is generally recognized that the long chain omega-3 EPA/DHA intake is more powerful in relation to cardiovascular disease and infl ammatory joint disease. 12,13,14 Even more important to appreciate are DHA’s unique health effects. Because it helps the eye, brain and nervous systems develop properly, infants have a special need for DHA. 15,16,17,18,19 Aging adults may need DHA, too, as it grants the most protection against Alzheimer’s disease.20 A FISH STORY Multiple clinical studies have shown the oils of fatty fi sh, EPA and DHA, to be of benefi t to the cardiovascular system, brain and visual function, immune Function, skin health, infl ammatory modulation and joint health.21,22 As ALA conversion to EPA is moderate at best, depending on many variables, and conversion to DHA is minimal, it is generally thought that regular, twice-weekly fatty fi sh oil consumption, or fi sh oil supplementation, are the best ways to enhance EPA/DHA status.23,24 However, the AHA warns that “some species of fi sh may contain signifi cant levels of methylmercury, polychlorinated biphenyls (PCBs), dioxins, and other environmental contaminants. These substances are present at low levels in fresh waters and oceans, … generally highest in older, larger, predatory fi sh and marine mammals.”25 The U.S. Environmental Protection Agency actually posts an advisory of fi sh consumption!26 Both the U.S. and Canada advise pregnant and nursing women, women who may become pregnant and young children to avoid eating certain fi sh.27,28 Fish oil capsules are the most concentrated form of omega-3 fats. Fortunately, few contain mercury. However, some may contain carcinogenic polychlorinated biphenyls (PCBs). Consumers who follow the label recommendation on some fi sh oil supplements can take in up to 43 per cent of the daily upper limit of PCBs!29 The biggest problem with deterioration in the quality of fi sh oil is rancidity from oxidation. Analytical assessments of oxidation are provided in terms of Peroxide Value (PV), Anisidine Value (AV), and Totox Value. However, the easiest test is the “taste test.” If the oil tastes or smells bad, it probably is bad, regardless of what the tests say.30 Because of the lipid peroxidation, it is generally recommended to take physiological doses of vitamin E when supplementing with fi sh oils.31,32 According to AHA guidelines, supplementing more than two grams of fi sh a day should be under a health professional’s guidance as it may lead to too much blood thinning and subsequent internal bleeding.33 We should not forget that fi sh is the major dietary source of vitamin D and yet is absent from most fi sh oils. As recent studies suggest that consuming more Vitamin D may lower the risk of death from any common disease of aging, especially colon and breast cancer, this is not an unimportant omission.34,35 Those fi sh oils, like cod liver oil, may have some vitamin D but may also have concomitantly high doses of vitamin A which may be contraindicated.36 Swallowing large or numerous fi sh oil pills and taste, texture and swallowing issues with fi sh oils, both including fi shy aftertaste and “fi sh burps”, can be a compliance hurdle. FACTORS IN FAVOUR OF FLAX Flaxseed is much more than just the richest source of ALA. Flaxseed is approximately 38 per cent oil, which is comprised mainly of alpha-linolenic acid, with lesser amounts of the omega-6 and omega-9 fatty acids. Not to be overlooked, is that fl axseed’s dietary fi bre content of about 28 per cent grants added health benefi ts. The American Dietetic Association has cited fi bre’s “signifi cant impact” on obesity, cardiovascular disease and Type 2 diabetes prevention and management.37 Flax has a ratio of soluble-to-insoluble fi bre that can vary in a ratio of between one part to four parts soluble-to-insoluble and four parts to six parts, respectively.38 Insoluble dietary fi bre supports healthy elimination and colon health, and may even have protective effects against colon cancer.39 The soluble dietary fi brefraction of fl ax is found primarily as mucilage gums, which have been shown to play a role in lowering serum cholesterol levels and glycemic control.40 Flax’s other very benefi cial compound is its lignans and fi bre. Lignans are a subclass of polyphenols known as phytoestrogens – plant compounds that can have estrogen-like actions.41 Through the actions of the lignans and ALA, fl ax may block tumour growth in animals and may help reduce breast, prostate and colon cancer risk in humans, likely by competing with toxic endogenous and xenogenous estrogens Flax consumption has been shown to lower blood cholesterol and C-reactive protein (CRP) levels – an infl ammatory marker – help reduce the risk of heart attacks and stroke, lower death rates for all causes of morbidity in cardiovascular disease patients, promote normal cardiac rhythm, and inhibit atherosclerosis. 47,48,49,50,51,52,53,54 Flax has even been associated with overall longevity. Alpha-linolenic acid may be especially important to vegans, vegetarians and people with low intakes of fatty fi sh. In those who ate little or no seafood, each 1- g/day increase in dietary ALA intake was associated with a 47 per cent reduction in the risk of coronary heart disease!55,56 It is apparent even from this briefest of introductory statements that the immune and cardio-protective benefi ts of a fl axseed-rich diet come from numerous salubrious mechanisms. VEGAN DHA Docosahexanoic (DHA), produced by marine micro-algae, is the vegetarian source of almost all of DHA in the bodies of sea creatures. DHA is the only omega-3 shown to provide brain, eye and heart health benefi ts in humans. Indeed, DHA is essential for the growth and function of the retina and brain of all humans, especially infants. (Human breast milk is rich in DHA.) The shorter chain n-3 fatty acid, alpha-linolenic acid (ALA), is not converted very well to the long chain DHA in humans. It should also be noted that the turnover of DHA in the brain is very fast, making regular intake vital DHA defi ciencies are associated with fetal alcohol syndrome, attention defi cit hyperactivity disorder (ADHD), cystic fi brosis, unipolar depression, aggressive hostility, Type 2 diabetes, cognitive decline during aging, Alzheimer’s disease and CVD.58 Increased DHA intake has a positive effect on diseases such as hypertension, arthritis, atherosclerosis, depression, adult-onset diabetes mellitus, myocardial infarction, thrombosis, and some cancers. DHA oil can reduce triglycerides, thrombosis and cardiac arrhythmias.59 Today, vegan DHA oil derived straight from marine micro-algae with excellent sensory characteristics can be harvested and extracted, under controlled conditions that are environmentally sustainable as relates to our overfi shed oceans – by avoiding killing large numbers of tuna, and other fi shes – and eliminates the risk of oceanic contamination with compounds such as PCBs and dioxins. Today, along with fl ax, marine algaederived DHA is being used more and more to fortify breads, cereals, juices, eggs, dairy products and functional foods. DESIGNER FUNCTIONAL FOOD: A SUPERFOOD SOLUTION? In view of the widespread reluctance of the public to consume suffi cient amounts of fi sh, and to a lesser extent fi sh oil supplements, functional foods containing fl ax, EPA and/or DHA are becoming increasingly important sources of these nutrients that support optimal brain/ visual performance, cardiovascular function, joint and skin health for young and old alike. While milled fl axseed provides many whole food benefi ts, its conversion to DHA is just too poor for fl ax to be considered the total answer for omega-3 supplementation. But new technologies now allow DHA from marine microalgae to be blended into crushed fl axseeds. Using nitrogen fl ush technologies in both blending and packaging allow the natural antioxidants in the fl ax to preserve the freshness of the vegan-sourced DHA. This results in the potential for the manufacture of new kinds of complete, great tasting omega-3 functional foods and supplements. Presuming such good taste, texture and ease of mixing, an interesting functional food supplement would be a combination of stabilized fl axseed, marine DHA from micro-algae, with synergistic vitamins D3, E, and some heart-healthy B complex. The natural rich antioxidants in the fl ax, like vitamin E (gamma tocopherol) and lignans, stabilize the long chain EPA/DHA. Functional food bars, candies, “ready-to-drink” products and powdered drink mixes, combining ALArich fl ax with vegetarian DHA, and perhaps even synergistic vitamins, are just now coming to market. Together with an effort to lower the intake of omega-6 fats from linoleic acid (LA)-rich vegetable oils (corn, saffl ower, sunfl ower), arachidonic acid (AA)-rich full-fat dairy and grain-fed animal fats, and “bad fats” like trans fats and rancid deep-fried fats, and with moderation in alcohol, these new “superfoods” may be part of the solution to returning our omega-3/omega-6 dietary ratios closer to those of our ancestors in a scientifi cally effi cacious, highly compliant, vegetarian, safe and environmentally sustainable way. • References: Please go to www.canadianchiropractor.ca and click on Current Issue to fi nd this article, complete with 59 references.