Greater consumption of oily fish and elevated blood levels of the very long-chain omega-3 polyunsaturated fatty acids, eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) are associated with a reduced incidence of heart attacks, arrhythmias, strokes, depression, cognitive decline and Alzheimer’s disease. Despite this stark reminder of the critical importance of the omega-3 fatty acids EPA and DHA, consumers consistently show low EPA+DHA status (Stark et al., 2016). Over 80% of the world population does not consume the recommended 250 mg EPA+DHA/d (Michaet al., 2014), predominantly due to low consumption of oily fish. A recent study found that just one-quarter of the UK population consumed oily fish, dropping to only 4.4% of 4 to 11-year-olds (Derbyshire, 2019).
EPA and DHA are important throughout life: in utero, in infancy, childhood, adulthood and into older age. As indicated above, EPA and DHA are particularly important for adults to promote cardiac and brain health. For children, EPA and DHA are considered especially important for the brain. A number of studies with children have demonstrated improvements in cognition and mental health in children whose oily fish intake, and blood DHA levels, increased (Sorensen et al., 2015; Teisen et al., 2020).
Up to now, oily fish such as salmon has been the major source of EPA and DHA. But given the insufficient intake of oily fish, we need to afford consumers more choice. To this end, we should consider the possibilities to bio-enrich more fish species and non-fish species with EPA and DHA. Humanativ was thus inspired to find a way of naturally enriching foods that are both widely consumed and relatively affordable – initially chicken and eggs, followed by turkey and pork, with work now continuing on lamb and veal.
The bioavailability of EPA and DHA from oily fish exceeds that of many supplements (Elvevoll et al., 2006). But is the DHA in non-traditional bio-enriched foods such as chicken and eggs bioavailable to consumers in the same way that it is in oily fish?
Animal nutrition specialists Devenish commissioned a double-blinded, randomized controlled study with the Royal College of Surgeons in Ireland to answer this question (Stanton et al., 2020). One hundred and sixty- one participants were split into four groups (Fig. 1). They each consumed at least three portions per week of chicken and eggs, either standard foods or naturally enriched with omega-3 DHA, for six months. The omega-3 DHA enriched chicken and eggs were achieved by including algal-derived omega-3 DHA (OmegaPro) in the diet of the animals.
Consumption of omega-3 DHA enriched chicken and eggs reduced by 65% the number of participants with a very low (=very high risk) omega-3 index (Fig. 2, colour red) and reduced blood pressure by 3 mm Hg. This would be expected to translate to a 15% reduction in cardiovascular mortality. The findings prove that similar to oily fish, the DHA in non-traditional bio- enriched foods such as chicken and eggs is bioavailable to consumers.
Consumer research conducted by Humanativ (June 2021) in the UK showed significant interest in the concept of omega-3 enriched chicken and eggs, with 73% of respondents interested in trying the product. It also showed there was a willingness, and expectation, that there would be a price premium for such a product. Interestingly, there was also a perception of higher welfare in animals fed a diet containing omega-3 DHA. This perception is well-founded, as well as providing a healthier product with increased levels of omega-3 DHA for the consumer, a number of advantages to the animals themselves have been observed when their diets include omega-3 DHA. In poultry, for example, a reduction in inflammation in the gastrointestinal tract was observed, accompanied by changes in the gut microbiome, namely reduced pathogenic bacteria and increased bacteria responsible for short-chain fatty acid production (McKenna et al., 2020).
Numerous studies on dietary omega-3 DHA have also shown improvements in poultry performance including growth rate, final body weight and feed conversion ratio. In fish species, EPA and DHA have been shown to be important across all life stages, supporting growth and development, health, and survival. It’s therefore little wonder that studies on the effects of omega-3 supplementation continue not only in fish but in other farmed species e.g. poultry, pork, lamb and veal that are not traditionally associated with being a source of omega-3 for consumers.
Traditionally, fish oil was used as the omega-3 DHA enrichment source. However, with a finite availability, and global expansion of the aquaculture industry, the need for alternative sources of long-chain omega-3 fatty acids in aquaculture is greater than ever.
Recent research has shown that algal oil provides several advantages over fish oil. High DHA algal oil reduces the inclusion rate in the diet and provides a highly consistent ingredient for feed formulation. Several studies have shown that issues with taste and taint in non-fish species can also be reduced with the use of algal oil compared to fish oil. In terms of sustainability, which is of increasing importance to consumers, algal oil is seen as a much more responsible source of omega-3 compared to fish oil, as it reduces the dependence on ocean catch.
Aquaculture provides more than 50% of the total global requirement of fish for human consumption and is playing an increasingly important role in global food security, providing a “superfood” that supplies high levels of essential nutrients and a rich source of EPA and DHA. While oily fish are seen as being the major source of EPA and DHA, other farmed species such as carp, tilapia and shrimp, which represent more than 80% of global aquaculture production, present a huge opportunity to ensure food and nutritional security for the wider global community. A number of studies have demonstrated the possibility of enriching tilapia and carp fillets with long-chain omega-3 fatty acids (Stoneham et al., 2018; Sobczak et al., 2020). These species also represent an opportunity for producers to further improve their value by increasing omega-3 content and achieving higher prices in the marketplace. Enriching more fish species, as well as non-fish species, with algal-derived omega-3 DHA will encourage greater consumption of this critically important nutrient. This has the potential to make a significant impact on health at a global level, and on healthcare budgets. If multiple options for consumers were available, making the healthy sustainable choice would increasingly become the easy choice.