Fishing for other sources of EFAs

Fish oils, algae-derived DHA and flaxseed are the leading providers of essential fatty acids. Their popularity has given rise to a broad swath of up-and-coming omega-3 ingredients, from fruit to nuts, said to provide the same benefits. Todd Runestad provides an overview of ingredients and their potential for the healthy-foods industry

So, you're a food manufacturer, and a savvy one at that. That means you know the difference between a fad and a trend — good thing you stayed on the sidelines of the low-carb fad, right? And if there's one unmistakable nutritional trend driving the food world today, you don't need to be a marketing whiz to know that it is omega-3 fatty acids. The US Food and Drug Administration gave them a health claim — it's like 2001 in the soy industry all over again! Only your staff scientist is confusing you because she's telling you it's not omega-3s per se but rather the omega-3 fatty acids DHA and EPA. And you say, aren't they all the same?

Chemistry — the arrangement of molecules — has, perhaps, never been so important as with the case of essential fatty acids. A fatty-acid molecule is a long hydrocarbon chain (hydrogen and carbon) capped by a carboxyl group (oxygen and hydrogen). Along that 18- to 22-carbon molecular chain, at least two bonds connect each carbon atom to one another. If the remaining two carbon bonds are linked with hydrogen atoms, that fatty acid is called saturated, and the resulting fat is solid at room temperature. If a carbon atom in that chain is double bonded, however, there will be room for only one hydrogen atom and, because of the missing hydrogen atom in the chain, the fatty acid is called unsaturated — liquid at room temperature. An unsaturated fatty acid containing just one double bond is called mono-unsaturated. More than one double bond — polyunsaturated.

Even smaller molecular differences can have profound health effects.

Take your garden-variety polyunsaturated hydrocarbon fatty-acid chain. If hydrogen atoms at two different double bonds along the chain are on the same side, the molecule is called a 'cis' configuration. But if hydrogen atoms at the double bonds are on opposite sides, it is called a 'trans' configuration. That simple change — the position of a single hydrogen atom at one point in an otherwise identical pair of 18-link hydrocarbon chains — can mean the difference between a relatively benign fat, and the cholesterol bomb known as a trans fat.

With omega-3 fatty acids, the number three represents the number of carbon atoms from the last double bond. Classic upstream metabolite alpha-linolenic acid (ALA), which converts to the all-important fatty acids eicosapentaenoic acid (20:5) and docosahexaenoic acid (22:6) — EPA and DHA — is often referred to as 18:3(n-3), meaning it has 18 carbon atoms with three double bonds.

It's a meaningful distinction because linoleic acid, which metabolises to omega-6 fatty acids gamma-linolenic acid and arachidonic acid, is routinely referred to as 18:2(n-6). The difference between an omega-6 and an omega-3 fatty acid — that is, an extra double bond with the number of carbon atoms from the last double bond at the sixth carbon instead of the third — can make all the difference in the world to a consumer interested in heart health, or any of a half-dozen other health benefits ascribed to EPA and DHA.

Linoleic acid is the precursor for the n-6 fatty acids; alpha-linolenic acid is the precursor for the n-3s EPA and DHA
Know thy fats
These fats are called essential because the body cannot create them on its own; it needs to get them from dietary sources. Essential fatty acids are needed in order to manufacture body lipids, biological membranes and hormonelike substances such as prostaglandins. Only two fatty acids are truly essential — linoleic acid and alpha-linolenic acid — with the remaining polyunsaturated fatty acids (PUFAs) derived from these by a sequence of desaturation and elongation steps. Linoleic acid is the precursor for the n-6 series of fatty acids, found primarily in plant oils, whereas alpha-linolenic acid is the precursor for the omega-3 series of fatty acids EPA and DHA that occur mainly in oily fish and, to a lesser extent, green leafy vegetables.

It is now well understood — certainly among the nutritional set, and to a lesser extent among consumers — that there are 'good' fats and 'bad' fats. Trans fats: bad. Omega-3 fats: good. But even that distinction does not clear the waters.

To receive the benefits of the n-3 fatty acids EPA and DHA, a human would have to get them from fish/fish oils or preformed DHA from algae sources as well as fortified foods (with EPA and DHA) — flaxseed oil has an inefficient conversion rate of linolenic acid to EPA and DHA of levels ranging from about 5-15 per cent for EPA and 2-5 per cent or even less for DHA.1,2,3,4,5,6 Indeed, the reason the FDA granted a qualified health claim for EPA and DHA from fish sources and explicitly not for flax is because of the fairly large evidence base for EPA and DHA compared to ALA. The main reason why ALA is so poorly converted to the longer-chain EPA and DHA is because it is mostly used for energy, and thus quickly removed from the blood, whereas EPA and DHA are not.

That is not to say that flaxseed is unhealthy — au contraire. Flaxseed has demonstrated the ability to modestly reduce serum total and LDL cholesterol, reduce post-meal glucose absorption, decrease some markers of inflammation, and serve as a good source of soluble fibre. Flax lignans have also been investigated for their efficacy toward hormonal conditions such as prostate and breast health.7,8 But flax does not have the same health benefits as fish-derived DHA and EPA when it comes to preventing second heart attacks, lowering triglyceride levels and offering other n-3 cardiovascular benefits.9,10

That flax is an omega-3 but will not get consumers appreciable quantities of EPA and DHA has created some confusion among food manufacturers, some of which have used flax in their products to boast the content of omega-3s. Consumers who are more familiar with the omega-3 term may believe by buying omega-3 foods they are getting the benefits of EPA and DHA. Different sources of omega-3s have different benefits, so source wisely.

Another variable compounding the benefits of n-3 oils is the fact that in the last half century, Western diets have consisted of larger amounts of highly processed foods. These contained decreased levels of omega-3s and increased levels of omega-6s. There was a time when the ratio of omega-6s to omega-3s in our diets was near 1:1. Today the typical Western diet has a ratio said to be 15:1 or higher. This imbalance promotes a range of chronic diseases from inflammation to cardiovascular disease, cancer, osteoporosis and more.11 In addition, because of competition between n-6 and n-3 sources, the ratio between the two is likely more important than the absolute amount of n-6 or n-3.12

Health benefits
Recognition of the health benefits of omega-3 fatty acids has grown since the Inuit Eskimos' low incidence of heart disease was highlighted in the 1970s.13 Their high-fat diet, sourced from marine animals, helped establish that the omega-3 fatty acids found in fish play a unique and important role in preventing heart disease.

The Italian GISSI trial represents the clinical trial with the longest duration (3.5 years), and the largest sample size (n=11,324), and that measured both LDL cholesterol and CHD in a diseased population. It reported a 15 per cent decrease in relative risk of coronary heart disease in the diseased-population intervention group, which had already suffered one heart attack, that consumed 1g/day omega-3 fatty acids.14

Lower triglyceride levels and a reduction of abnormal thickening of arteries due to fatty plaque deposits on arterial inner walls seem to be two primary means of fish oils having their beneficial effect on cardiovascular health.15

Despite the FDA failing to throw its full weight behind omega-3 EFAs, in Europe there is no such hesitation. A recent International Herald Tribune article reported that every patient in the cardiac care unit at the San Filippo Neri Hospital in Rome who survives a heart attack goes home with a prescription for purified fish-oil capsules.

Of note to formulators, a 2006 human study discovered that a combined supplement containing omega-3s, vitamin E and niacin — all with documented cardiovascular effects — acts together at different levels of lipid-chain production to improve the lipid profile, inflammation and oxidative status, allowing researchers to reduce the dose of each compound. In niacin's case, the dosage was still effective without any of niacin's side effects.16

Stroke-risk reduction can also be conferred by fish consumption. Harvard researchers found that any fish consumption at all will decrease stroke risk by 12 per cent, with each additional single serving of fish per week further decreasing stroke risk by two per cent.17

Heart health is hardly the end of this fish tale. Many other benefits have also been associated with consumption of fish oils, spanning the entire life, from pregnancy and infants, to joint health, cognitive function and certain cancers.

Pregnancy and infants
DHA is a major structural fatty acid in the grey matter of the brain and the retina of the eye, comprising up to 20 per cent of total fatty acids in the brain and up to 50 per cent in the retina.18 It is naturally found in breast milk. DHA has been found to be important for visual and mental development of the infant in utero and throughout infancy.19

DHA was cited as the likely component of breast milk influencing the significantly higher cognitive outcomes of breast-fed infants through the first 18 years of life, as compared to non-DHA supplemented formula-fed infants.20 Indeed, a recent Harvard study estimates that increasing maternal DHA intake by 100mg/day increases child IQ by 0.13 points.21 DHA supplementation resulted in mental-development advantages in children including improved eye-hand co-ordination and improved attention skills as toddlers.22,23

The amount of time a foetus spends in utero can have profound implications for the health of the infant. A Danish study of 533 pregnant women who supplemented 2.7g/day n-3 fatty acids found the treated group had a significant four days extra gestation compared to placebo.24 Remaining in utero benefits the infant. And having the mother supplement with DHA can have positive effects on an infant's growth, visual acuity and multiple indices of development, according to a randomised, masked, controlled trial on mothers supplementing with arachidonic acid and DHA.25

Inflammation is part of the body's normal response to infection and injury. However, excessive or inappropriate inflammation contributes to a range of acute and chronic human diseases and is characterised by the production of inflammatory cytokines, arachidonic acid-derived eicosanoids (prostaglandins, thromboxanes, leukotrienes), and inflammatory free radicals.26 DHA and EPA are direct precursors for series-3 prostaglandins, which are hormonelike substances that can reduce platelet aggregation, or blood clotting, as well as improve blood flow and reduce inflammation.27

Resolvins are lipids within EPA and DHA — identified by researchers only in 2000 — that directly reduce inflammation
Omega-3s suppress the synthesis and release of pro-inflammatory cytokines such as tumour necrosis factor alpha, interleukin-1 and interleukin-2. In only 2000, researchers for the first time identified lipids within EPA and DHA, dubbed 'resolvins,' which are produced by EPA and directly reduce inflammation. 28 The precursor n-3 PUFA alpha-linolenic acid does not appear to exert anti-inflammatory effects at achievable intakes.

Brain and behaviour
Results from controlled treatment trials investigating the efficacy of DHA/EPA on children's behavioural issues, in particular ADHD, are mixed, but the few studies in this area have involved different populations and treatment formulations. Dietary supplementation with fish oils appears to alleviate ADHD-related symptoms in at least some children, and one study of ADHD children also found benefits for academic achievement.29 In a preliminary trial to investigate which forms of fatty acids might work best, 30 adults with ADHD were randomly assigned to 12 weeks of supplementation with olive oil (which contains less than one percent omega-3 fatty acids), flax oil (a good source of alpha-linolenic acid), or fish oil (high in both EPA and DHA). Blood levels of fatty acids were measured at the start of the trial and again after 12 weeks. While flax oil supplementation resulted in an increase in ALA and a slight decrease in the ratio of omega-6 to omega-3 fatty acids, fish-oil supplementation brought about significant increases in EPA, DHA and total omega-3 fatty acids, as well as a decrease in the ratio of omega-6s to omega-3s. This suggests that fish oil may be more effective in improving fatty-acid profiles and therefore alleviating the symptoms of ADHD.30

In a placebo-controlled, double-blind study on physical aggression in children nine to 12 years old, 3.6g/day fish oils for three months reduced physical aggression in girls, but not boys.31

Autism is a condition characterised by a marked impairment in social interaction, delayed language use and restrictred patterns of behaviour. One recent study gave 13 autistic children five to 17 years old 1.5 g/day PUFAs of placebo for six weeks. The supplementing children had significant decreases in hyperactivity and repetitive movements compared to placebo.32

Low omega-3 levels have been linked to depression in elderly people.33 EPA may be more important than DHA in treating depression. This was teased out of a double-blind, placebo-controlled study in the US.34 Another interesting study found a low-dose omega-3 supplement had better results than a high-dose supplement.35 While additional research comes in, provocative new evidence has shown that DHA and arachidonic acid may help slow cognitive decline in the elderly.36 Other research from 2006 shows the n-3 oils may slow mental decline in people with very mild Alzheimer's disease — but no effect on people with more advanced forms.37 Although there is no known cause for Alzheimer's as of yet, researchers speculate that because DHA is the most abundant fat in the brain, low levels of the fatty acid may somehow play a role in disease formation.

Healthier bones
Animal studies, and now recent human studies, suggest a role in bone health as well, particularly in relation to abnormally high levels of omega-6 fatty acids. A long-term study in California tracked the ratio of dietary omega-6 fats to omega-3s in relation to bone-mineral density (BMD) in middle- and older-age individuals. They tested BMD by dual-energy X-ray absorptiometry?the gold standard for assessing bone loss?and found that the higher the ratio of linoleic acid (omega-6) to alpha-linolenic acid (omega-3), the lower the BMD. These results were independent of age, body mass index and various lifestyle factors.38

Preventing cancer
Evidence is beginning to accumulate that the omega-3s work on a genetic level to prevent cancer development by increasing the expression of tumour suppression genes BRCA1 and BRCA2, which help repair damaged DNA. Some animal studies show that diets high in n-6 fatty acids — which roughly correlate to the highly processed current Western diets — set the stage for cancer later in life. If these animal studies are extrapolated to humans, it may explain the link among diet, early puberty onset and breast-cancer risk, and indicate that an in utero exposure to a diet high in n-6 PUFAs may affect later breast-cancer risk.39

This research is both preliminary and equivocal — some rat studies show that although prepubertal exposure to a low-fat n-3 PUFA diet reduced later mammary tumorigenesis in rats, high levels of this fatty acid can have adverse effects on the prepubertal mammary gland and increase subsequent breast-cancer risk. 40

More to come
Evidence has also emerged showing benefits from n-3 fatty acid consumption in health conditions such as lupus and asthma.41,42 A cross-sectional study in Australia showed an inverse association between fish consumption and age-related maculopathy (ARM) — a leading cause of blindness in older adults. Subjects who ate fish more than once per week reduced their risk of having ARM by half compared to those who ate fish less than once per month.43 Patients with rheumatoid arthritis, who received fish-oil supplements in addition to background medication, had a significant decrease in the number of tender joints and morning stiffness.44 The continued study of n-3 fatty acids will lead to further understanding of their effects on development, health and disease-risk reduction.

Recent food innovations are conveniently allowing consumers the choice of healthier foods, in particular those fortified with omega-3 fatty acids. DHA-infused eggs are created by feeding chickens flaxseed, kelp, canola or other nonanimal fats. New technologies allow the easy integration of fish oils into a range of foods and beverages. Seed oils already have a relatively simple way of getting into baked goods. Ultimately, through a combination of supplementation of clean, high-quality fish-oil capsules as well as pumping up foods with various sources of omega-3 fatty acids, may the health of consumers finally begin to improve.

Fish oils get a run for their money from other omega-3 sources

Arizona Chia: Chia, salvia hispanica L, contains the highest known plant source of omega-3 fatty acids. It is also rich in dietary fibre (soluble and insoluble), antioxidants, vitamins, and minerals. Unlike flax it does not need to be ground prior to eating, but if ground it will last for months on your countertop because the seed contains natural antioxidants. Chia can be consumed in many ways, sprinkled on salads, mixed in yoghurt or cereals (hot or cold), baked in breads, or mixed with water or juices. or

Bioriginal: BioAsteri borage oil, BioFlaxElite flax and BioPure fish-head oil are part of the Canadian company's complete line of vegetarian and fish-sourced omega-3s, which are used in nutraceuticals, functional foods, skin-care products, cosmetics, animal feed, veterinary products and over-the-counter pharmaceuticals.

Cognis: Omevital omega-3 fish oil, available in high concentrates of up to 60 per cent combined EPA/DHA, was launched in 2006 following its acquisition of Norwegian supplier Napro Pharma.

Croda Health Care: Incromega TG triglyceride range has high-potency EPA and DHA concentrates. Incromega omega-3 concentrates provide EPA up to 70 per cent purity to target inflammatory conditions. Crossential omega-6 concentrates provide 25-40 per cent GLA for atopic eczema and PMS. A vegetarian source of EPA from stearidonic acid-rich echium oil is on its way to market.

Decas Cranberry Products: OmegaCran oil, derived from cranberry seeds using a cold-press expeller process, has many of the benefits of omega-3 and omega-6 fatty acids without the taste of fish oil. The sweetened dried cranberries can be used in snacks, cereals, yoghurt, and salads.

Denomega: Omega-3 DHA/EPA concentrations vary from 10 per cent to 40 per cent for dairy-based foods and beverages. Denomega omega-3 powder is used for baked goods, its omega-3 liquid for fruit-based beverages and other challenging applications.

DSM: ROPUFA range of PUFAs come in the form of chemically unmodified but highly refined vegetable and marine oils. Powder forms are used mainly in dry goods such as bakery products and baby food. They are dispersible in cold water, are exceptionally stable, and have a neutral taste and odour.

EPAX: The Norwegian company offers concentrated EPA/DHA oils in a wide range of formulas with different EPA/DHA ratios focused on specific health conditions. EPAX is also available in triglyceride or ethyl-ester versions.

Europharma: Vectomega is a patented cold-water and enzyme process by which it extracts omega-3s from Atlantic salmon without destroying the composition of the natural phospholipids. Launched as an ingredient in dry water-soluble powder form, the Vectomega process uses no heat, solvents or chemical modifications, giving it a positive natural profile. Company research shows 50 per cent more DHA and EPA crosses cell membranes compared to other products available at retail, making it cheaper than many other fish-oil forms.

Firmenich: Duralife Omega 3 is fish-sourced EPA and DHA with a proprietary encapsulation technology to protect it from degradation, and suitable for instant hot- and cold-drink powders, cereal dry mixes, compressed tablets, and more.

Flavex: Kiwifruit Omega 3 contains more than 65 per cent omega-3s in the form of alpha-linolenic acid and about 15 per cent omega-6s as linoleic acid, which differentiates it from other plant sources. The German company is introducing a pomegranate oil in 2007.

Frutarom: The Israeli ingredients firm supplies salvia-seed oil as a source of omega-3 fatty acid alpha-linoleic acid. Salvia contains 60 per cent ALA, compared to flaxseed oil's 50 per cent.

Jedwards International: Supplier of EPA and DHA fish oils, cod-liver oil, and GLA and omega-3-rich seed oils including borage, primrose, flax and more, to the food, supplements and cosmetics industries in North America.

Light Heart: Heartbran R is a novel patented food ingredient combination of whole rice bran, vitamins and omega-3 fish oil in a stabilised, bland-tasting powder system. It is suitable for snacks, cereal, drinks and nutrition bars.

Loders Croklaan: Marinol fish-oil concentrates from Lipid Nutrition division in glyceride form has application in functional foods, medical foods, enteral food and infant nutrition.

Lonza: Lonza DHA FO is an algae-derived, vegetarian-source DHA food oil for use in food applications. Lonza DHA CL is a clear oil especially developed for use in dietary supplements. The recent acquisition of the DHA business from Nutrinova includes know-how, patents and registrations in the major global markets that apply.

Martek Biosciences: life'sDHA brand algae-derived DHA is king of infant formula and is making inroads into other foods, such as General Mills and Kellogg's cereals, Hain-Celestial products, and a new 15-year deal with WhiteWave. Martek's DHA is made from algae, the only vegetarian source with meaningful amounts of DHA.

Neptune Technologies and Bioresources: Neptune Krill Oil (NKO) uses oil from krill, a crustacean rich in EPA, DHA, phospholipids and antioxidants. A partnership with Terepia has led to fruit-flavoured custards using NKO for yoghurts, baby formulas, cereals, bars and more.

Nu-Mega: HiDHA tuna oil uses a microencapsulation technology to convert its HiDHA tuna oil into a stable dry powder form called Driphorm.

Ocean Nutrition Canada: The Meg-3 brand, based on Powder-loc micro-encapsulation technology, provides double-shell protection that keeps the EPA/DHA from fish oils locked into the microcap while keeping the smell and taste of the fish locked out of the food.

Omega Protein OmegaPure: This menhaden fish oil is a rich source of long-chain omega-3 EPA and DHA.

Pharmalink: Lyprinol contains lipids extracted from the New Zealand green-lipped mussel (Perna canaliculus). These omega-3 mussels are also rich in iron, betain and clycoaminoglycans including chondroitin sulphate.

Pizzey's Milling: Using a patented process to protect flaxeed's omega-3 oils makes its milled flaxseed ingredients the most oxidatively stable omega-3 ingredients for baked applications.

Polar Foods: HiOmega 70% ALA omega-3 flax oil contains no hexane or solvents, nor do its other ingredients food-grade HiOmega 70% ALA omega-3 refined flaxseed oil and regular 58% ALA omega-3 flaxseed oil.

Pronova Biocare, Omacor: With 90 per cent EPA ethyl ester as the active, this is also an Rx drug in the US for high-triglyceride patients.

Puleva Biotech: It signed an agreement with US-based The Wright Group for its Eupoly EPA/DHA fish oils to be used in a new line of micro-encapsulated powders in June 2006.

Valensa International: Z-omega fish-oil analogue combines botanical omega-3 extracts with astaxanthin and other antioxidants to support cardiovascular health. Valensa's Tresalbio is a plant-sourced omega-3 derived from Salvia hispanica seed extract.

Vegelip: Vegelip brand omega-3 gel oil harnesses the technology to replace animal-derived trans and saturated fats in a range of foods with a gel made from healthy oils such as canola, flax, fish or marine oils. The gel is texturized, thermoresistant and thermo-irreversible.

The Wright Group: O-3 Complete uses SuperCoat micro-encapsulation technology to allow delivery of fish oils in a dry powder to prevent oxidation and increase shelf life. One powder delivers a 2:1 ratio of EPA to DHA, the other a 2:1 ratio of DHA to EPA. Custom powders are available.

An interview with Manny Sabares, director of marketing at Bioriginal

FF&N: Bioriginal offers flax, borage, evening primrose and also fish, blackcurrant, perilla and hemp as EFA sources. Does the company market each ingredient differently for different applications?

MS: At Bioriginal we don't just provide ingredients — we're a complete EFA solutions provider. Our ingredients are marketed on the basis of their unique benefits, not any specific application. Each ingredient is available in a variety of different formats, to fit custom-specific applications.

Branding has become an important part of our marketing strategy and our branded portfolio currently includes BioAsteri borage oil, BioPureDHA fish oil and BioFlaxElite flax products. By looking at branding from an ingredient perspective, our customers can capitalize on the unique features of our range to offer truly unique products.

FF&N: What does the recent launch of BioPureDHA fish oil do to round out the Bioriginal portfolio of EFA ingredients?

MS: We're always looking to increase and enhance our offerings by adding new omega fatty-acid sources to our portfolio. There is a growing body of research supporting DHA and its potential to improve mental health. Consequently, we are seeing an increase in DHA products targeted at learning and focus in children, and adult mental health.

FF&N: What does the future of delivery system/food and beverage offerings look like?

MS: New technology, advanced micro-encapsulation and innovative processing techniques have allowed easier incorporation of EFAs into a variety of food and beverage products. This trend is set to continue. As the market progresses, we believe that growth will be two-fold — in both functional foods and dietary supplements. The functional-food trend complements the dietary supplements market.

FF&N: Are consumers buying 'omega-3s' that are integrated into processed food products or is flax riding the coattails of fish-derived EPA/DHA?

MS: According to the NMI, 69 per cent of consumers associate one major health benefit with omega-3s. This is not source dependent. Both fish and plant oils are essential in optimal health, with each different ingredient offering unique health benefits. The key is to educate consumers on the importance of a balance of all omega-3s and omega-6s in maintaining optimal health.

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