Within the UK, dietary intakes of long chain omega-3 fatty acids are well below current recommended levels for optimal cardiovascular health. Whilst adequate intake of the long chain omega-3 fatty acids eicosapentaenoic acid (EPA) and docosahexaenoic acids (DHA) can be achieved by eating fatty fish at least 1–2 times per week, (equivalent to 250–500mg/d of EPA and DHA) the majority of us fail to achieve such intake. The cardiovascular health properties of fish oil are attributed to its enrichment in EPA and DHA but for vegetarians and vegans, for whom marine sources of omega-3 are not an option, sourcing effective amounts of omega-3 can be challenging.
Many vegetarians and vegans turn to algae sources of preformed EPA and DHA; when it comes to heart health, however, it seems that algae oil may not be the best option. The majority of algae oils are high in DHA with little or no EPA content. Several studies have recently shown that oils that are high in DHA can increase the amount of LDL or ‘bad’ cholesterol within our blood and that, as such, pure EPA oils may fair significantly better when attempting to lower both triglyceride and cholesterol levels (Bays et al, 2011). When LDL cholesterol levels are too high, the LDL lipoprotein can stick to the lining of the blood vessels and in time can lead to atherosclerosis – the development of sticky plaques that can build up and obstruct the normal blood flow In contrast, another type of cholesterol HDL lipoprotein ’scours’ the walls of blood vessels, removing excess cholesterol. What is becoming clear is that whilst EPA and DHA lower triglyceride levels (high triglycerides can lead to type II diabetes and raise the risk of heart disease), only EPA increases good HDL cholesterol and lowers bad LDL cholesterol. Ideally, vegetarians and vegans who are seeking to supplement with omega-3 for optimal heart health should therefore seek oils containing EPA but which are free from DHA. Flaxseed oil contains significant amounts of alpha-linolenic acid (ALA), the precursor to EPA. Our ability to modify and convert ALA to EPA, however, is significantly restricted with less than 8% of ALA metabolised to EPA.
In contrast, echium seed oil, unlike flaxseed or algae oil has the potential to significantly reduce plasma triglyceride and cholesterol levels, and the risk of atherosclerosis (Forrest et al, 2011). Echium oil, derived from the seeds of Echium plantagineum, contains 12–14% of total fatty acids as stearidonic acid (SDA) the immediate product of ALA and the direct precursor to EPA. Recent findings suggest that even a low daily intake of SDA, easily achievable through dietary means, has the potential to raise tissue membrane levels of EPA (Krul et al, 2011).
Echium seed oil is, not surprisingly, generating a lot of interest as a ‘fish-oil alternative’ for vegetarians and vegans. Offering known benefits for health and the cardiovascular system, echium seed oil, with its unique fatty acid composition, offers a myriad of health benefits (Whelan et al, 2011; Chilton et al, 2008) making it a superior choice of omega-3 for those who choose not to consume fish or fish oils.
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2. Forrest LM, Boudyguina E, Wilson MD, Parks JS. Echium oil reduces atherosclerosis in apoB100-only LDLrKO mice. Atherosclerosis 2011.
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