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I’ve got some good news, and some bad news for you vegetarians and vegan types out there. First, the bad news: That flaxseed oil you’ve been relying on for your daily dose of omega-3? It’s not a good substitute for fish oil.
Omega-3 fatty acids consist of eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA), and alpha-linolenic acid (ALA). For most people, the main source of omega-3 in their diet comes from fatty fish, such as salmon.
EPA and DHA
Often, vegetarians, however, rely almost exclusively on flax oil for their omega-3 supplementation – this is a mistake because flax oil consists solely of ALA, which must first be converted into EPA, and then subsequently converted into DHA. In-so-far as meeting dietary requirements of omega-3, DHA and EPA are the only real players here that matter. At least in most respects. We’ll get to the exceptions on that in a minute.
Although ALA can be converted into EPA and DHA in your body, several studies have shown this to be a very inefficient process. 1 In fact, the human body can only convert very small amounts of ALA into EPA and DHA. Studies have shown that only approximately 5% of ALA is converted to EPA, whereas, less than 0.5% is converted in to DHA. 2
The reason for this inefficiency is due to the rate limiting step: enzyme availability. This is because the enzyme responsible for the conversion of ALA into EPA, delta-6-desaturase, competitively binds to omega-6 fatty acids also. Hence, in order to get DHA from flax-derived ALA, your body must undergo not one, but two rate limiting enzymatic conversions: first from ALA to EPA, then from EPA to DHA.
Clearly this is, as stated earlier, a terribly inefficient process that could be circumnavigated entirely simply by going right to the source and ingesting EPA and DHA directly.The good news is there IS a source of omega-3 that qualifies as vegetarian, won’t offend your moral or dietary sensibilities, has a high grade of purity, and avoids depleting fish stocks…two words: microalgae oil.
Microalgae Oil Supplementation
Something many of you might not know is that algae, such as zooplankton and phytoplankton, are actually the primary source of EPA and DHA omega-3 fatty acids. Fish ingest these microalgae and store the DHA and EPA in their fat, which is why fish oil is high in both of these omega-3 fatty acids. 3
Some microalgae have already been shown to produce high levels of both DHA and EPA, such as Spirulina and Nannochloropsis sp., however, high-EPA microalgae supplements are still in short supply. Even so, switching to microalgae removes at least one enzymatic step – which, apparently, makes all the difference in the world.
In one study, vegetarians that were deficient in EPA and DHA, took 1 gram of microalgae oil daily. 4 After eight weeks, they significantly raised both their DHA and EPA levels. This is in stark contrast to another study that showed that ALA derived from flax oil did not significantly increase EPA and DHA levels. 5
In another, similar example lactating women supplementing with 10.7g per day with ALA derived from flaxseed oil, failed to increase DHA levels in their breast milk. 6 This is particularly alarming for any nursing mothers relying on flaxseed as their omega-3 source because DHA is the most abundant fatty acid in the brain, particularly during development — a time when the availability of all the essential building blocks of life are most important. 7
Moreover, during fetal development in particular, DHA must be obtained through the mother’s circulation and reduced DHA levels leads to visual and learning deficits. 10
Now, with that said, ALA supplementation does have benefits that are distinct from DHA and EPA which, quite specifically, pertains to the skin
ALA Omega 3
Perhaps the most recognizable function of ALA that is separable from other omega-3 fatty acids is its role in the skin. More than 46% of ALA was found in the skin and fur of guinea pigs that were orally administered ALA. 11
Additionally, ALA was shown to promote fur growth in rats, indicating that ALA plays an essential role in hair growth. 12 The effects of ALA deficiency were studied in monkeys and resulted in skin lesions and fur loss, which was restored upon ALA supplementation. 13
Topical application of ALA has also been shown to lighten skin after UV-induced hyperpigmentation and this was due to decreased melanin production as well as increased desquamation of pigment in the epidermis. 14
The bottom line is that ALA derived from flaxseed oil is not an adequate vegetarian source for DHA and EPA, and those should ultimately be supplemented separately from ALA/Flaxseed Oil. Microalgae oil is a good source of DHA and EPA for vegetarians for this. Flaxseed oil, isn’t, however, without its own beneficial effects and might still make a good supplement in addition to whatever else you choose to make your primary source of EPA and DHA.