Omega-3 fatty acids are amongst the most researched nutrients, and have been shown to be a wellspring of nutritional value. They are also a polyunsaturated fatty acid, which makes them a type of fat.
Fat is a valuable macronutrient, which we all need to be able to live a healthy life. The confusing thing can be understanding how much fat we should have, and which fats they should be in order to ensure that we remain healthy.
Fish oil has become one of those key areas of debate. Lots of research has shown the positive impact which fish oil may have on health and disease prevention due to the high levels of omega-3 fatty acids it contains. However, environmental research has shown that the demand for fish oil is destroying marine habitats and ecosystems, and polluting the oceans to the extent that contaminants and heavy metals are present in many fish-derived supplements.
This guide will focus on EPA and DHA, two essential omega-3 fatty acids, their value to our health and wellbeing, how they are treated in the body, and sustainable methods of supplementation which don’t involve fish.
What are essential fatty acids?
When a nutrient or substance is classed as ‘essential’ it means that the human body is unable to produce it, and that we need to get it from our diet. There are two completely essential fatty acids that we must obtain from food. These are linoleic acid (LA), which is an omega-6 fatty acid, and alpha-linoleic acid (ALA), an omega-3 fatty acid.
There are four other essential fatty acids which can lower our need to ingest LA and ALA, which are:
- arachidonic acid (AA)
- gamma-linolenic acid (GLNA)
- eicosapentaenoic acid (EPA)
- docosahexaenoic acid (DHA)
If you’re not ingesting or including these four fatty acids in your diet, then your need to eat foods containing LA and ALA will increase.
In this article, we will be focusing on EPA and DHA. They are both omega-3 fatty acids, which can be obtained from oily fish, algae, or via supplementation. If not ingested through diet, EPA and DHA are synthesised from ALA. In terms of biological function, ALA helps to provide the body with energy, and not much more. However, because it can be converted into DHA and EPA, which do have essential biological functions, it is classed as an essential fatty acid.
Why do we need EPA and DHA?
Omega-3 fatty acids have innumerate health benefits, and insufficient levels can cause deficiencies which carry their own risks, including changes to our eyes, neurological functioning (such as a decreased ability to focus and concentrate), and can also have an impact on our joints, energy levels, and ability to get a good night’s rest.
In particular, insufficient levels of EPA and DHA in the human bloodstream have been found to increase the risk of heart disease through excessive blood clotting. DHA in good levels, on the other hand, have been shown to lower triglyceride levels, which are a risk factor for cardiovascular problems and heart disease (Bernstein et al., 2012).
DHA serves as a structural component in cell membranes, especially in the nerve cells in our brains and eyes. It makes up about 40% of the polyunsaturated fats in your brain (Singh, 2005). Therefore, insufficient levels of DHA in blood have been shown to impair neurological function, including the onset of depression and anxiety symptoms, and impaired cognitive abilities. EPA is particularly effective against certain neurological conditions, particularly alleviating the symptoms of depression and anxiety (Sublette et al., 2011).
EPA forms signalling molecules called eicosanoids, which can help to reduce inflammation (Siriwardhana, Kalupahana and Moustaid-Moussa, 2012), and it has also been shown to have a positive impact on the pain and swelling caused by both rheumatoid arthritis and reducing menstrual pain (Zafari, Behmanesh and Agha Mohammadi, 2011)
DHA is vital during pregnancy and breastfeeding for foetal brain and eye development, the development of the nervous system and the prevention of developmental delays (Bernardi et al., 2012) (Agostoni et al., 1997). The importance of EPA and DHA doesn’t stop after birth. In children, DHA and EPA have been shown to significantly reduce the symptoms of ADHD and may also help to prevent asthma (Sonuga-Barke et al., 2013) (Li et al., 2012).
How much EPA and DHA do I need?
The European Food Safety Authority, along with other authorities worldwide, recommend a minimum of 250-500mg of combined EPA and DHA per day with an extra 200mg of DHA for women who are pregnant or breastfeeding. For ALA, the recommended daily intake is 1.1g for women, and 1.6g for men. (European Food Safety Authority, n.d.)
When a nutrient’s absorption profile is affected by the synthesis of other substances or illness, they are known as ‘conditionally essential’. DHA and EPA are thought to be conditionally essential, because the conversion process from ALA is inefficient, especially for DHA. One study suggests that the conversion rate may be as low as 5% of EPA from ALA and 0.5% of DHA from ALA. Most of the ALA you ingest will be used for energy, so it’s important to make sure that you’re getting enough DHA and EPA from other sources (Plourde and Cunnane, 2007).
Are there any factors which affect the synthesis of DHA and EPA from ALA?
As with any nutrient, there are many things which can affect the way they are produced, absorbed or used. With EPA and DHA synthesis from ALA, these are some factors to consider:
- Age: As with many other nutrients, our body’s ability to synthesise DHA and EPA from ALA lessens as we age, meaning that older people might require more of both fatty acids in their diet, or via supplement.
- Biological sex: Women have a notably higher converstion rate than men do, which is believed to be related to the presence of oestrogen in the body. Not only does this mean that women need less ALA than men, and can produce more DHA and EPA from higher quantities of ALA, it’s also been suggested that this might be why women tend to have a lower risk of developing heart disease than men (Burdge, 2004).
- Presence of other fats: If your diet is high in saturated fats, then your body’s ability to convert ALA into EPA and DHA can be impaired. This is also true for anyone with a diet high in omega-6 fatty acids. LA, another essential fatty acid mentioned earlier, uses the same enzymes when converting into arachidonic acid (AA) as ALA does to convert into DHA and EPA. This causes a direct competition for those enzymes in the body, which may negatively impact conversion rates (Ap, 2002).
- Low intakes of DHA and EPA: Not getting enough DHA and EPA from your diet increases the demand for conversion from ALA.
How do I make sure I get enough EPA and DHA?
For vegans and vegetarians, the idea of consuming fish oil supplements in order to achieve this is problematic, and more than a little gross.
There are ways of adding plant-based ALA to your diet, including through flaxseeds, chia seeds, and walnuts, but with the conversion process being as limited as research has shown it to be, and DHA and EPA being so vital to our health and wellbeing, it’s important that we get enough.
This is where algae comes in - you see, fish don’t naturally make their own EPA and DHA, they source it through food from marine algae. It becomes more concentrated in larger fish as they consume multiple smaller fish who all have levels of EPA and DHA from algae.
That’s why Vivo Life created their Vegan Liquid Omega-3 Supplement. It’s made from sustainably grown algae, and provides 300mg of EPA and 600mg of DHA per serving. As the algae is grown in tanks, the resulting omega-3 supplement is purer and cleaner than those derived from fish oil, is third party tested to ensure that there are no contaminants or heavy metals present, and has a fresh lemon taste rather than a fishy one!
Siriwardhana, N., Kalupahana, N.S. and Moustaid-Moussa, N. (2012). Health Benefits of n-3 Polyunsaturated Fatty Acids. Marine Medicinal Foods - Implications and Applications - Animals and Microbes, [online] pp.211–222. doi:10.1016/b978-0-12-416003-3.00013-5.
Sublette, M.E., Ellis, S.P., Geant, A.L. and Mann, J.J. (2011). Meta-analysis of the effects of eicosapentaenoic acid (EPA) in clinical trials in depression. The Journal of Clinical Psychiatry, [online] 72(12), pp.1577–1584. doi:10.4088/JCP.10m06634.
Bernardi, J.R., Escobar, R. de S., Ferreira, C.F. and Silveira, P.P. (2012). Fetal and Neonatal Levels of Omega-3: Effects on Neurodevelopment, Nutrition, and Growth. The Scientific World Journal, 2012, pp.1–8. doi:10.1100/2012/202473.
Bernstein, A.M., Ding, E.L., Willett, W.C. and Rimm, E.B. (2012). A meta-analysis shows that docosahexaenoic acid from algal oil reduces serum triglycerides and increases HDL-cholesterol and LDL-cholesterol in persons without coronary heart disease. The Journal of Nutrition, [online] 142(1), pp.99–104. doi:10.3945/jn.111.148973.
Theodoratou, E., McNeill, G., Cetnarskyj, R., Farrington, S.M., Tenesa, A., Barnetson, R., Porteous, M., Dunlop, M. and Campbell, H. (2007). Dietary Fatty Acids and Colorectal Cancer: A Case-Control Study. American Journal of Epidemiology, 166(2), pp.181–195. doi:10.1093/aje/kwm063.
MASTERTON, G.S., PLEVRIS, J.N. and HAYES, P.C. (2010). Review article: omega-3 fatty acids - a promising novel therapy for non-alcoholic fatty liver disease. Alimentary Pharmacology & Therapeutics, 31(7), pp.679–692. doi:10.1111/j.1365-2036.2010.04230.x.
Zafari, M., Behmanesh, F. and Agha Mohammadi, A. (2011). Comparison of the effect of fish oil and ibuprofen on treatment of severe pain in primary dysmenorrhea. Caspian Journal of Internal Medicine, [online] 2(3), pp.279–282. Available at: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3770499/.
Sonuga-Barke, E.J.S., Brandeis, D., Cortese, S., Daley, D., Ferrin, M., Holtmann, M., Stevenson, J., Danckaerts, M., van der Oord, S., Döpfner, M., Dittmann, R.W., Simonoff, E., Zuddas, A., Banaschewski, T., Buitelaar, J., Coghill, D., Hollis, C., Konofal, E., Lecendreux, M. and Wong, I.C.K. (2013). Nonpharmacological Interventions for ADHD: Systematic Review and Meta-Analyses of Randomized Controlled Trials of Dietary and Psychological Treatments. American Journal of Psychiatry, 170(3), pp.275–289. doi:10.1176/appi.ajp.2012.12070991.
Agostoni, C., Trojan, S., Bellu, R., Riva, E., Bruzzese, M.G. and Giovannini, M. (1997). Developmental quotient at 24 months and fatty acid composition of diet in early infancy: a follow up study. Archives of Disease in Childhood, 76(5), pp.421–424. doi:10.1136/adc.76.5.421.
Li, J., Xun, P., Zamora, D., Sood, A., Liu, K., Daviglus, M., Iribarren, C., Jacobs, D., Shikany, J.M. and He, K. (2012). Intakes of long-chain omega-3 (n−3) PUFAs and fish in relation to incidence of asthma among American young adults: the CARDIA study. The American Journal of Clinical Nutrition, 97(1), pp.173–178. doi:10.3945/ajcn.112.041145.
European Food Safety Authority. (n.d.). Scientific Opinion on the Tolerable Upper Intake Level of eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA) and docosapentaenoic acid (DPA). [online] Available at: https://www.efsa.europa.eu/en/efsajournal/pub/2815.
Burdge, G. (2004). Alpha-Linolenic acid metabolism in men and women: nutritional and biological implications. Current Opinion in Clinical Nutrition and Metabolic Care, 7(2), pp.137–144. doi:10.1097/00075197-200403000-00006.
Ap, S. (2002). The Importance of the Ratio of omega-6/omega-3 Essential Fatty Acids. [online] Biomedicine & pharmacotherapy = Biomedecine & pharmacotherapie. Available at: https://pubmed.ncbi.nlm.nih.gov/12442909/.
Plourde, M. and Cunnane, S.C. (2007). Extremely limited synthesis of long chain polyunsaturates in adults: implications for their dietary essentiality and use as supplements. Applied Physiology, Nutrition, and Metabolism = Physiologie Appliquee, Nutrition Et Metabolisme, [online] 32(4), pp.619–634. doi:10.1139/H07-034.