According to the Academy of Nutrition and Dietetics, well-planned vegetarian or vegan diets are healthy and nutritionally adequate for all stages of the life cycle, as well as for athletes (Melina, 2016). However, some nutrients such as omega-3 fatty acids may be in deficit. EPA and DHA are two omega-3 essentials for cardiovascular, brain, and eye health.
OMEGA-3 FATTY ACIDS: ALA, EPA, AND DHA
There are two essential fatty acids: linoleic acid (LA), from the omega-6 family, and alpha-linolenic acid (ALA), from the omega-3 family. LA and ALA are essential because our body cannot synthesize them. Both AL and ALA could convert to other long-chain polyunsaturated fatty acids. From alpha-linolenic acid (ALA), our body can synthesize EPA and then DHA.
The transformation from ALA to EPA is, however, generally less than 10% in humans and from ALA to DHA is negligible (Harris, 2014; Melina, 2016; Rogerson 2017).
ALA is found in plant foods such as nuts, flax and chia seeds, hemp oil, rapeseed, and soybeans; while EPA and DHA are found in seaweeds and fish and shellfish. Thus, the intake of ALA is similar in vegetarians and non-vegetarians, but the levels of EPA and DHA is low in vegetarians and virtually nil in vegans.
IMPORTANCE OF EPA AND DHA FATTY ACIDS
Given the importance of EPA and DHA fatty acids in cell functioning and, in the case of DHA, in brain structure, neuronal and nervous transmission and transduction of visual signals, it is necessary to ensure the contribution of these compounds, especially DHA, through the intake of fish or in the case of vegetarian and vegan diets through the consumption of seaweed, enriched food or vegan food supplements. (García, 2016; Saunders 2012).
DHA SUPPLEMENTS FOR VEGETARIANS AND VEGANS
According to the American Dietetic Association, DHA supplements derived from microalgae are well absorbed and positively influence blood levels of DHA and also EPA through retro-conversion. DHA supplements derived from microalgae are the best option for vegetarians and vegans. These supplements are highly suitable for women during pregnancy and lactation; people with diabetes, metabolic syndrome or hypertension; and elderly people (Saunders, 2012).
WHAT IF I ALSO TAKE AN EPA SUPPLEMENT?
EPA supplementation results in an increase of EPA in plasma but not DHA. However, supplementation with DHA produces higher levels of DHA plasma and a modest rise in EPA, indicating an efficient retro-conversion of DHA to EPA (Garcia, 2016). The intake of omega-3 fatty acids in vegetarian and vegan diets can thus be achieved by combining ALA rich-food sources with a DHA supplement from microalgae oil. 600 mg of microalgae oil or one capsule of Optim DHAlg provides 250mg of DHA, the daily recommended intake (EFSA 2017).
García A, Dalmau S. Ácido docosahexaenoico. ¿Un ácido graso omega-3 esencial? Acta Pediatr Esp. 2016;74(3-4):101-106.
Harris WS. Achieving optimal n-3 fatty acid status: the vegetarian’s challenge… or not. Am J Clin Nutr. 2014 Jul;100 Suppl 1:449S-52S.
Melina V, Craig W, Levin S. Position of the Academy of Nutrition and Dietetics: Vegetarian Diets. J Acad Nutr Diet 2016 Dec;116(12):1970-1980.
Rogerson, D. Vegan diets: practical advice for athletes and exercisers. J Int Soc Sports Nutr. 2017 Sep 13;14:36.
Saunders AV, David BC, Garg ML. Omega-3 polyunsatured fatty acids and vegetarian diets. Med J Aust. 2013 Aug 19;199(4 Suppl):S22-6.