Who Should Take Algal Oil?
The two major classes of polyunsaturated fatty acids (PUFAs) are omega-3 and omega-6 fatty acids.[1] Deficiency of omega-3 is an issue for people who consume a diet without fish, as oily fish are the main dietary source of omega-3 fatty acids.[2] Not only does this include vegans and vegetarians, but individuals with seafood allergies and those who do not eat fish for other reasons.
Vegan diets contain excessive amounts of the omega-6 linoleic acid (LA) and are typically void of long-chain omega-3 fatty acids, eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). As a result, vegans are at risk of EPA and DHA deficiency and an imbalanced omega-6-to-omega-3 ratio. Moreover, there are few vegan sources that are both rich in the plant omega-3, alpha-linoleic acid (ALA), and low in the plant omega-6, LA[3] to help skew this balance towards the ideal 4-to-1 ratio.[4] And finally, LA competes with enzymes in the body that synthesise EPA and DHA from ALA,[5] making it even more difficult to obtain long-chain omega-3 fatty acids from dietary sources.
Algal oil supplementation can provide an alternative solution since long-chain omega-3 fatty acids are originally produced by microalgae, not by fish.[6],[7] Schizochytrium sp. algal oil, for example, provides a rich and bioavailable source of DHA.[8],[9],[10]
At present, there is evidence to support the use of supplemental omega-3 fatty acids for the following indications:
- during pregnancy to prevent preterm birth,[11]
- to support infant and child brain health,[12]
- to help protect against food allergy in infants,[13]
- as an adjuvant treatment for depression,[14]
- to enhance mood and cognition,[15]
- to reduce inflammatory pain,[16] and
- to help preserve muscle mass and strength as we age.[17],[18]
Associations between fish consumption or omega-3 status also proposes that supplementation may be indicated for children and adolescents at risk of asthma, rhinitis and aeroallergen sensitisation;[19] for sleep in children and adolescents;[20] for individuals at risk of depression;[21] and to promote heart,[22],[23],[24] brain[25] and eye health.[26],[27]
Research has identified several key conditions in which algal oil supplementation may be beneficial. First and foremost, individuals with who have a poor omega-6-to-omega-3 ratio, which arguably includes almost anyone eating a Western diet. The majority of people can benefit from more omega-3 fatty acids, not just vegans. In fact, only 20% of the Australian population meet the recommended omega-3 fatty acid intake for optimal health.[28] With the Western diet, the omega-6-to-omega-3 ratio is disproportionately high (≥20-to-1), and promotes obesity and cardiovascular disease (CVD), cancer, and inflammatory and autoimmune conditions.[29],[30],[31]
In one randomised, double-blind, placebo-controlled, crossover trial (n=116), algal DHA (250 mg/day) effectively increased serum DHA and reduced the omega-6-to-omega-3 fatty acid ratio in lacto-ovo vegetarians, vegans and omnivores. In the case of vegans, changes in serum % DHA doubled compared to placebo and baseline.[32]
An older and smaller double-blind study (n=24) found that algal DHA (1620 mg/day) dramatically increased serum DHA (+246%), and significantly lowered total-to-high-density lipoprotein (HDL) [-16%] and low-density lipoprotein (LDL)-to-HDL (-22%) cholesterol ratios in vegetarians.[33] Similar findings have been reported throughout the literature at various doses of algal DHA (i.e. 172 to 2140 mg) noting considerably increases in circulating DHA levels.[34]
Pregnant and breastfeeding women can benefit from algal oil supplementation. It is important to first mention that only 10% of Australian women of childbearing age meet the recommended DHA intake.[35] That alone provides reason to supplement.
A randomised, double-blind trial (n=1100) showed that a higher dose algal DHA supplementation (1000 mg/day) was superior to 200 mg/day during pregnancy for lowering early preterm birth (1.7% versus 2.4%). This was especially true of women who had low DHA status at enrolment (2.0% versus 4.1%).[36]
A phase II, randomised, double-blind, placebo-controlled trial (n=350) reports that algal DHA (600 mg/day) led to increased maternal (2.6%; p<0.001) and cord red blood cell (RBC)-phospholipid-DHA (1.4%; p=0.001); longer gestation duration (2.9 days; p=0.041); and greater birth weight (172 g; p=0.004), length (0.7 cm; p=0.022) and head circumference (0.5 cm; p=0.012). In addition, the DHA group had fewer early preterm births (4.8% versus 0.6%; p=0.025) and shorter hospital stays for infants born preterm (40.8 compared with 8.9 days; p=0.026) than the placebo group.[37]
Additionally, DHA-rich algal oil (1200 mg/day) has been shown to significantly increase the content of DHA and EPA of breast milk in mothers who delivered prematurely. In this clinical trial (n=461), algal oil significantly reduced DHA-to-arachidonic acid (AA) and omega-6-to-omega-3 fatty acid ratios, which could modify the regulation of inflammation.[38]
Multiple trials report that algal DHA (400 to 1200 mg/day) produces subtle but favourable effects on at least one area of cognition or behaviour in healthy children (aged 4 to 10 years), i.e., sustained attention, listening comprehension, vocabulary acquisition, or reading underperformance.[39],[40],[41],[42] Other evidence suggests that higher blood levels of DHA may relate to better child sleep and that algal DHA (600 mg/day) can help, specifically by leading to fewer and shorter night-waking episodes and longer sleep duration. However, further research is needed to lend strength to these findings.[43]
Microalgae DHA (2110 mg/day) has been shown to ameliorate disease activity (i.e. tender and swollen joints) in rheumatoid arthritis (RA) patients. In this pilot study (n=38), algal oil shifted the balance of AA- and DHA-derived lipid mediators towards an anti-inflammatory/pro-resolving state, alongside regular medication.[44]
In a clinical study in healthy older adults with age-related cognitive decline (ARCD) [n=485, aged ≥55 years], algal DHA (900 mg/day) improved learning and episodic memory functions.[45]
As can be said of omega-3 fatty acids, algal oil appears to be beneficial for improving health across the lifespan. Not only does it play a role in the prevention of chronic inflammatory diseases, but it may also enhances health outcomes in pregnant women and their infants from childhood through to adolescence, as well as promoting healthy ageing. Individuals who are not getting enough omega-3 fatty acids from their diet stand to benefit from a supplemental source of omega-3 fatty acids, such as algal oil. This does not exclusively concern vegans and vegetarians but extends to individuals who are not consuming the recommended 2 to 3 serves of fish per week,[46] i.e., the majority of the Australian population.[47]
References
[1] Office of Dietary Supplements. Omega-3 fatty acids [Internet]. Bethesda: National Institutes of Health; 2023 [cited 2024 Mar 25]. Available from: https://ods.od.nih.gov/factsheets/Omega3FattyAcids-HealthProfessional/
[2] Burdge GC, Tan SY, Henry CJ. Long-chain n-3 PUFA in vegetarian women: a metabolic perspective. J Nutr Sci. 2017;6:e58. DOI: 10.1017/jns.2017.62
[3] Burns-Whitmore B, Froyen E, Heskey C, Parker T, San Pablo G. Alpha-linolenic and linoleic fatty acids in the vegan diet: do they require dietary reference intake/adequate intake special consideration? Nutrients. 2019 Oct;11(10):2365. DOI: 10.3390/nu11102365
[4] Burns-Whitmore B, Froyen E, Heskey C, Parker T, San Pablo G. Alpha-linolenic and linoleic fatty acids in the vegan diet: do they require dietary reference intake/adequate intake special consideration? Nutrients. 2019 Oct;11(10):2365. DOI: 10.3390/nu11102365
[5] Burns-Whitmore B, Froyen E, Heskey C, Parker T, San Pablo G. Alpha-linolenic and linoleic fatty acids in the vegan diet: do they require dietary reference intake/adequate intake special consideration? Nutrients. 2019 Oct;11(10):2365. DOI: 10.3390/nu11102365
[6] Office of Dietary Supplements. Omega-3 fatty acids [Internet]. Bethesda: National Institutes of Health; 2023 [cited 2024 Mar 25]. Available from: https://ods.od.nih.gov/factsheets/Omega3FattyAcids-HealthProfessional/
[7] Matos ÂP. The impact of microalgae in food science and technology. J Am Oil Chem Soc. 2017 Sep;94:1333-1350. DOI: 10.1007/s11746-017-3050-7
[8] Saini RK, Prasad P, Sreedhar RV, Akhilender Naidu K, Shang X, Keum YS. Omega-3 polyunsaturated fatty acids (PUFAs): emerging plant and microbial sources, oxidative stability, bioavailability, and health benefits-a review. Antioxidants (Basel). 2021 Oct;10(10):1627. DOI: 10.3390/antiox10101627
[9] Ryan L, Symington AM. Algal-oil supplements are a viable alternative to fish-oil supplements in terms of docosahexaenoic acid (22:6n-3; DHA). J Funct Foods. 2015;19:825-858. DOI: 10.1016/j.jff.2014.06.023
[10] Martins DA, Custódio L, Barreira L, Pereira H, Ben-Hamadou R, Varela J, et al. Alternative sources of n-3 long-chain polyunsaturated fatty acids in marine microalgae. Mar Drugs. 2013 Jun;11(7):2259-2281. DOI: 10.3390/md11072259
[11] Middleton P, Gomersall JC, Gould JF, Shepherd E, Olsen SF, Makrides M. Omega-3 fatty acid addition during pregnancy. Cochrane Database Syst Rev. 2018 Nov;11(11):CD003402. DOI: 10.1002/14651858.CD003402.pub3
[12] Lepping RJ, Honea RA, Martin LE, Liao K, Choi IY, Lee P, et al. Long-chain polyunsaturated fatty acid supplementation in the first year of life affects brain function, structure, and metabolism at age nine years. Dev Psychobiol. 2019 Jan;61(1):5-16. DOI: 10.1002/dev.21780
[13] Clausen M, Jonasson K, Keil T, Beyer K, Sigurdardottir ST. Fish oil in infancy protects against food allergy in Iceland-results from a birth cohort study. Allergy. 2018 Jun;73(6):1305-1312. DOI: 10.1111/all.13385
[14] Sarris J, Murphy J, Mischoulon D, Papakostas GI, Fava M, Berk M, et al. Adjunctive nutraceuticals for depression: a systematic review and meta-analyses. Am J Psychiatry. 2016 Jun;173(6):575-587. DOI: 10.1176/appi.ajp.2016.15091228
[15] Fontani G, Corradeschi F, Felici A, Alfatti F, Migliorini S, Lodi L. Cognitive and physiological effects of omega-3 polyunsaturated fatty acid supplementation in healthy subjects. Eur J Clin Invest. 2005 Nov;35(11):691-699. DOI: 10.1111/j.1365-2362.2005.01570.x
[16] Goldberg RJ, Katz J. A meta-analysis of the analgesic effects of omega-3 polyunsaturated fatty acid supplementation for inflammatory joint pain. Pain. 2007 May;129(1-2):210-223. DOI: 10.1016/j.pain.2007.01.020
[17] Therdyothin A, Phiphopthatsanee N, Isanejad M. The effect of omega-3 fatty acids on sarcopenia: mechanism of action and potential efficacy. Mar Drugs. 2023 Jul;21(7):399. DOI: 10.3390/md21070399
[18] Dupont J, Dedeyne L, Dalle S, Koppo K, Gielen E. The role of omega-3 in the prevention and treatment of sarcopenia. Aging Clin Exp Res. 2019 Jun;31(6):825-836. DOI: 10.1007/s40520-019-01146-1
[19] Magnusson J, Ekström S, Kull I, Håkansson N, Nilsson S, Wickman M, et al. Polyunsaturated fatty acids in plasma at 8 years and subsequent allergic disease. J Allergy Clin Immunol. 2018 Aug;142(2):510-516.e6. DOI: 10.1016/j.jaci.2017.09.023
[20] Jansen EC, Conroy DA, Burgess HJ, O'Brien LM, Cantoral A, Téllez-Rojo MM, et al. Plasma DHA is related to sleep timing and duration in a cohort of Mexican adolescents. J Nutr. 2020 Mar;150(3):592-598. DOI: 10.1093/jn/nxz286
[21] Grosso G, Micek A, Marventano S, Castellano S, Mistretta A, Pajak A, et al. Dietary n-3 PUFA, fish consumption and depression: a systematic review and meta-analysis of observational studies. J Affect Disord. 2016 Nov;205:269-281. DOI: 10.1016/j.jad.2016.08.011
[22] Zhang B, Xiong K, Cai J, Ma A. Fish consumption and coronary heart disease: a meta-analysis. Nutrients. 2020 Jul;12(8):2278. DOI: 10.3390/nu12082278
[23] Mahajan H, Choo J, Masaki K, Fujiyoshi A, Guo J, Evans R, et al. Serum long-chain n-3 polyunsaturated fatty acids and aortic calcification in middle-aged men: the population-based cross-sectional ERA-JUMP study. Nutr Metab Cardiovasc Dis. 2019 Aug;29(8):837-846. DOI: 10.1016/j.numecd.2019.04.011
[24] He K, Song Y, Daviglus ML, Liu K, Van Horn L, Dyer AR, et al. Accumulated evidence on fish consumption and coronary heart disease mortality: a meta-analysis of cohort studies. Circulation. 2004 Jun;109(22):2705-2711. DOI: 10.1161/01.CIR.0000132503.19410.6B
[25] Schaefer EJ, Bongard V, Beiser AS, Lamon-Fava S, Robins SJ, Au R, et al. Plasma phosphatidylcholine docosahexaenoic acid content and risk of dementia and Alzheimer disease: the Framingham Heart Study. Arch Neurol. 2006 Nov;63(11):1545-1550. DOI: 10.1001/archneur.63.11.1545
[26] Zhu W, Wu Y, Meng YF, Xing Q, Tao JJ, Lu J. Fish consumption and age-related macular degeneration incidence: a meta-analysis and systematic review of prospective cohort studies. Nutrients. 2016 Nov;8(11):743. DOI: 10.3390/nu8110743
[27] SanGiovanni JP, Chew EY. The role of omega-3 long-chain polyunsaturated fatty acids in health and disease of the retina. Prog Retin Eye Res. 2005 Jan;24(1):87-138. DOI: 10.1016/j.preteyeres.2004.06.002
[28] Meyer BJ. Australians are not meeting the recommended intakes for omega-3 long chain polyunsaturated fatty acids: results of an analysis from the 2011-2012 National Nutrition and Physical Activity Survey. Nutrients. 2016 Feb;8(3):111. DOI: 10.3390/nu8030111
[29] Simopoulos AP. The importance of the ratio of omega-6/omega-3 essential fatty acids. Biomed Pharmacother. 2002 Oct;56(8):365-379. DOI: 10.1016/s0753-3322(02)00253-6
[30] Simopoulos AP. An increase in the omega-6/omega-3 fatty acid ratio increases the risk for obesity. Nutrients. 2016 Mar;8(3):128. DOI: 10.3390/nu8030128
[31] Simopoulos AP. Evolutionary aspects of diet, the omega-6/omega-3 ratio and genetic variation: nutritional implications for chronic diseases. Biomed Pharmacother. 2006 Nov;60(9):502-507. DOI: 10.1016/j.biopha.2006.07.080
[32] García-Maldonado E, Alcorta A, Zapatera B, Vaquero MP. Changes in fatty acid levels after consumption of a novel docosahexaenoic supplement from algae: a crossover randomized controlled trial in omnivorous, lacto-ovo vegetarians and vegans. Eur J Nutr. 2023 Jun;62(4):1691-1705. DOI: 10.1007/s00394-022-03050-3
[33] Conquer JA, Holub BJ. Supplementation with an algae source of docosahexaenoic acid increases (n-3) fatty acid status and alters selected risk factors for heart disease in vegetarian subjects. J Nutr. 1996 Dec;126(12):3032-3039. DOI: 10.1093/jn/126.12.3032
[34] Craddock JC, Neale EP, Probst YC, Peoples GE. Algal supplementation of vegetarian eating patterns improves plasma and serum docosahexaenoic acid concentrations and omega-3 indices: a systematic literature review. J Hum Nutr Diet. 2017 Dec;30(6):693-9. DOI: 10.1111/jhn.12474
[35] Meyer BJ. Australians are not meeting the recommended intakes for omega-3 long chain polyunsaturated fatty acids: results of an analysis from the 2011-2012 National Nutrition and Physical Activity Survey. Nutrients. 2016 Feb;8(3):111. DOI: 10.3390/nu8030111
[36] Carlson SE, Gajewski BJ, Valentine CJ, Kerling EH, Weiner CP, Cackovic M, et al. Higher dose docosahexaenoic acid supplementation during pregnancy and early preterm birth: a randomised, double-blind, adaptive-design superiority trial. EClinicalMedicine. 2021 Jun;36:100905. DOI: 10.1016/j.eclinm.2021.100905
[37] Carlson SE, Colombo J, Gajewski BJ, Gustafson KM, Mundy D, Yeast J, et al. DHA supplementation and pregnancy outcomes. Am J Clin Nutr. 2013 Apr;97(4):808-815. DOI: 10.3945/ajcn.112.050021
[38] Fougère H, Bilodeau JF, Lavoie PM, Mohamed I, Rudkowska I, Pronovost E, et al. Docosahexaenoic acid-rich algae oil supplementation on breast milk fatty acid profile of mothers who delivered prematurely: a randomized clinical trial. Sci Rep. 2021 Nov;11(1):21492. DOI: 10.1038/s41598-021-01017-8
[39] Richardson AJ, Burton JR, Sewell RP, Spreckelsen TF, Montgomery P. Docosahexaenoic acid for reading, cognition and behavior in children aged 7-9 years: a randomized, controlled trial (the DOLAB Study). PLoS One. 2012;7(9):e43909. DOI: 10.1371/journal.pone.0043909
[40] Kuratko CN, Barrett EC, Nelson EB, Salem N. The relationship of docosahexaenoic acid (DHA) with learning and behavior in healthy children: a review. Nutrients. 2013 Jul;5(7):2777-2810. DOI: 10.3390/nu5072777
[41] McNamara RK, Able J, Jandacek R, Rider T, Tso P, Eliassen JC, et al. Docosahexaenoic acid supplementation increases prefrontal cortex activation during sustained attention in healthy boys: a placebo-controlled, dose-ranging, functional magnetic resonance imaging study. Am J Clin Nutr. 2010 Apr;91(4):1060-1067. DOI: 10.3945/ajcn.2009.28549
[42] Ryan AS, Nelson EB. Assessing the effect of docosahexaenoic acid on cognitive functions in healthy, preschool children: a randomized, placebo-controlled, double-blind study. Clin Pediatr (Phila). 2008 May;47(4):355-362. DOI: 10.1177/0009922807311730
[43] Montgomery P, Burton JR, Sewell RP, Spreckelsen TF, Richardson AJ. Fatty acids and sleep in UK children: subjective and pilot objective sleep results from the DOLAB study--a randomized controlled trial. J Sleep Res. 2014 Aug;23(4):364-388. DOI: 10.1111/jsr.12135
[44] Dawczynski C, Dittrich M, Neumann T, Goetze K, Welzel A, Oelzner P, et al. Docosahexaenoic acid in the treatment of rheumatoid arthritis: a double-blind, placebo-controlled, randomized cross-over study with microalgae vs. sunflower oil. Clin Nutr. 2018 Apr;37(2):494-504. DOI: 10.1016/j.clnu.2017.02.021
[45] Yurko-Mauro K, McCarthy D, Rom D, Nelson EB, Ryan AS, Blackwell A, et al. Beneficial effects of docosahexaenoic acid on cognition in age-related cognitive decline. Alzheimers Dement. 2010 Nov;6(6):456-464. DOI: 10.1016/j.jalz.2010.01.013
[46] Heart Foundation. Dietary position statement: fish, seafood & heart healthy eating – updated 2015 [Internet]. Docklands: National Heart Foundation of Australia; 2015 [cited 2024 Mar 21]. Available from: https://www.heartfoundation.org.au/bundles/for-professionals/nutrition-position-statements
[47] Meyer BJ. Australians are not meeting the recommended intakes for omega-3 long chain polyunsaturated fatty acids: results of an analysis from the 2011-2012 National Nutrition and Physical Activity Survey. Nutrients. 2016 Feb;8(3):111. DOI: 10.3390/nu8030111