Omega-3 fatty acid
Common name Alternative name Linnaean name % ALA
Kiwifruit seed oil Chinese gooseberry Actinidia deliciosa 63
Perilla shiso Perilla frutescens 61
Chia seed chia sage Salvia hispanica 58
Flax linseed Linum usitatissimum 53 - 59
Lingonberry Cowberry Vaccinium vitis-idaea 49
Fig seed oil Common Fig Ficus carica 47.7
Camelina Gold-of-pleasure Camelina sativa 36
Purslane Portulaca Portulaca oleracea 35
Black raspberry Rubus occidentalis 33
Hemp Cannabis sativa 19
Canola Rapeseed oil mostly Brassica napus 9 - 11
Dietary sources -- Plant sources
Chia is grown commercially for its seeds rich in ALA . Flax seeds contain linseed oil which has high ALA content Table 1 . ALA content as the percentage of the seed oil . [ 123 ]
Omega−3 fatty acids, also called ω−3 fatty acids or n−3 fatty acids, are polyunsaturated fatty acids (PUFAs) characterized by the presence of a double bond three atoms away from the terminal methyl group in their chemical structure. They are widely distributed in nature, being important constituents of animal lipid metabolism, and they play an important role in the human diet and in human physiology. The three types of omega−3 fatty acids involved in human physiology are α-linolenic acid (ALA), found in plant oils, and eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), both commonly found in marine oils. Marine algae and phytoplankton are primary sources of omega−3 fatty acids. Common sources of plant oils containing ALA include walnut, edible seeds, clary sage seed oil, algal oil, flaxseed oil, Sacha Inchi oil, Echium oil, and hemp oil, while sources of animal omega−3 fatty acids EPA and DHA include fish, fish oils, eggs from chickens fed EPA and DHA, squid oils, krill oil, and certain algae. Mammals are unable to synthesize the essential omega−3 fatty acid ALA and can only obtain it through diet. However, they can use ALA, when available, to form EPA and DHA, by creating additional double bonds along its carbon chain (desaturation) and extending it (elongation). Namely, ALA (18 carbons and 3 double bonds) is used to make EPA (20 carbons and 5 double bonds), which is then used to make DHA (22 carbons and 6 double bonds). The ability to make the longer-chain omega−3 fatty acids from ALA may be impaired in aging. In foods exposed to air, unsaturated fatty acids are vulnerable to oxidation and rancidity. Dietary supplementation with omega−3 fatty acids does not appear to affect the risk of death, cancer or heart disease. Furthermore, fish oil supplement studies have failed to support claims of preventing heart attacks or strokes or any vascular disease outcomes.