Omega-3 Fatty Acids

Omega-3 Fatty Acids

What is Omega-3?

Omega-3 are polyunsaturated fats. You do not make Omega-3 in your body so you must get them from your diet. They help build the support structure in every cell of your body. Omega-3 gives you energy and helps your heart, lungs and immune system work effectively.

Some foods that contain omega-3 fatty acids include:

  • Salmon
  • Trout
  • Herring
  • Sardines
  • Tuna
  • Anchovies
  • Flounder
  • Beans
  • Canola oil
  • Chia seeds
  • Walnuts

There are three main types of Omega-3s:

  • Eicosapentaenoic acid (EPA)
  • Docosahexaenoic acid (DHA)
  • Alpha-linolenic acid (ALA)

Your body needs Omega-3 fatty acids to function. Omega-3 fatty acids are thought to help heart health and brain development, protect from autoimmune diseases and cancer and decrease depression and inflammation.

Inflammation

One study carried out a placebo-controlled, double blind, 12-week randomised control trial that compared Omega-3 supplementation with placebos. The study involved 68 medical students who provided blood samples during lower periods of stress and periods of high stress (days before an exam). The students either received the Omega-3 supplement or the placebo. The results found that students who received the Omega-3 supplement showed a 14% decrease in lipopolysaccharide stimulated interleukin production (which promotes the bodies inflammatory response) and a 20% reduction in anxiety symptoms compared to those who took the placebo supplement (Kiecolt-Glaser et al., 2011). 

The study presented is concrete because randomised control trials are the gold standard of research as they limit the influence of extraneous variables impacting results. Some people may argue that a 20% or a 14% reduction is not a significant reduction. However, for taking one supplement a day, it is quite cost-effective.  

Cardiovascular diseases

There is quite a lot of research into Omega-3 consumption and cardiovascular diseases. Albert et al. (1998)concluded that consuming fish at least once per week may reduce the risk of sudden cardiac death and this may be due to their Omega-3 content. Another study supports Albert’s conclusion as they found long-term fish consumption decreased coronary heart disease and myocardial infarction risk (Streppel et al., 2008). One study specifically looked into Omega-3 consumption and coronary heart disease in women and concluded that higher intake of Omega-3 fatty acids lowered the risk of coronary heart disease (Hu et al., 2002).

de Goede et al. (2010) conducted a study that investigated populations with low fish consumption and showed that EPA and DHA supplements may lower fatal coronary heart disease and myocardial infarction. This may suggest that effects of supplementation may depend upon how much fish you are consuming.

Cancer

Omega-3 consumption has been shown to influence different types of cancers too. In general, frequent fish consumption, irrespective of cooking method, may reduce the risk of lung cancer (Takezaki et al., 2003).

Fish consumption has also been linked to prostate cancer. Research suggests that men who eat no fish are two to three times more likely to get prostate cancer than those who eat fish in moderate or high amounts (Terry et al., 2001).

Depression

There have been mixed results for Omega-3 supplementation’s effect on depression. One study which looked into supplementing a moderate dose of Omega-3 in healthy adults who had a low-intake of Omega-3 fatty acids for 18 weeks, showed that it did not alter impulsive behaviours, corticolimbic (emotion and behaviour) and corticostriatal (reward-processing) brain functionality (Ginty et al., 2017).

However, other studies show otherwise. One study found that supplementation of Omega-3 fatty acids may improve depressive symptoms (Mazereeuw et al., 2017). It is also suggested that Omega-3 fatty acids are an effective treatment for depression but its effects are dependent upon the persons baseline level of Omega-3 fatty acids (Carney et al., 2016).

Brain development

Omega-3 has also been associated with brain development. Fish oil supplements have been connected with significantly lower mean cognitive subscale of the Alzheimer’s Disease Assessment Scale and higher mini-mental state examination scores among those with normal cognition (Daiello et al., 2014). The same study also found that fish oil supplements were associated with less atrophy in at least one brain region.

Furthermore, weekly consumption of baked or broiled fish is related to larger grey matter volume independent of Omega-3 fatty acid content (Raji et al., 2014). One study looked at 1319 participants from 9 studies, 700 of them received an Omega-3 supplement and 376 received a placebo. The results indicated that ingestion of Omega-3 fatty acids increases learning, memory, cognitive well-being and blood flow in the brain (Dighriri et al., 2022).

Bioavailability of Omega-3

In terms of the bioavailability of Omega-3, research is very mixed. A review of the biochemistry research of Omega-3 fatty acids summaries that opinions on the bioavailability of Omega-3 fatty acids remains ‘’divided’. The review also states that the bioavailability of Omega-3 is dependent upon the specificity of blood transport and the fat content in the food (Cholewski et al., 2018).

Another study reviewed 13 articles regarding the bioavailability of plant-sourced Omega-3 fatty acids. The study found that high dose flaxseed or echium seed oil supplements provide no increase in Omega-3 and that microalgal oil supplementation increased Omega-3 levels for all studies reviewed (Lane et al., 2022).

Conclusion

Omega-3 fatty acids have been stated to improve a range of things in the human body. The research highlighted in this article suggests that Omega-3 fatty acids improve brain functioning, reduces inflammation and protects you from cardiovascular diseases as well as certain types of cancer and may even be a treatment for depression.

However, most of the research notes regularly consuming fish as part of your diet which, when considering the factors that influence the bioavailability of Omega-3 fatty acids, may be why it is best to get it from your diet. If you struggle getting Omega-3 fatty acids as part of your diet, then there seems to be no harm in supplementation. The research also suggests that if following a vegan or vegetarian diet, getting your Omega-3 fatty acids from flaxseed or echium oil supplements is not the way to go and you should consider a microalgal oil supplement.

 

 

References

Albert, C. M., Hennekens, C. H., O’Donnell, C. J., Ajani, U. A., Carey, V. J., Willett, W. C., Ruskin, J. N., & Manson, J. E. (1998). Fish consumption and risk of sudden cardiac death. JAMA, 279(1), 23–28. https://doi.org/10.1001/jama.279.1.23

Carney, R. M., Steinmeyer, B. C., Freedland, K. E., Rubin, E. H., Rich, M. W., & Harris, W. S. (2016). Baseline blood levels of omega-3 and depression remission: A secondary analysis of data from a placebo-controlled trial of omega-3 supplements. The Journal of Clinical Psychiatry, 77(2), e138-143. https://doi.org/10.4088/JCP.14m09660

Cholewski, M., Tomczykowa, M., & Tomczyk, M. (2018). A Comprehensive Review of Chemistry, Sources and Bioavailability of Omega-3 Fatty Acids. Nutrients, 10(11), Article 11. https://doi.org/10.3390/nu10111662

Daiello, L. A., Gongvatana, A., Dunsiger, S., Cohen, R. A., & Ott, B. R. (2014). Association of fish oil supplement use with preservation of brain volume and cognitive function. Alzheimer’s & Dementia : The Journal of the Alzheimer’s Association, 11(2), 226. https://doi.org/10.1016/j.jalz.2014.02.005

de Goede, J., Geleijnse, J. M., Boer, J. M. A., Kromhout, D., & Verschuren, W. M. M. (2010). Marine (n-3) fatty acids, fish consumption, and the 10-year risk of fatal and nonfatal coronary heart disease in a large population of Dutch adults with low fish intake. The Journal of Nutrition, 140(5), 1023–1028. https://doi.org/10.3945/jn.109.119271

Dighriri, I. M., Alsubaie, A. M., Hakami, F. M., Hamithi, D. M., Alshekh, M. M., Khobrani, F. A., Dalak, F. E., Hakami, A. A., Alsueaadi, E. H., Alsaawi, L. S., Alshammari, S. F., Alqahtani, A. S., Alawi, I. A., Aljuaid, A. A., & Tawhari, M. Q. (2022). Effects of Omega-3 Polyunsaturated Fatty Acids on Brain Functions: A Systematic Review. Cureus, 14(10), e30091. https://doi.org/10.7759/cureus.30091

Ginty, A. T., Muldoon, M. F., Kuan, D. C. H., Schirda, B., Kamarck, T. W., Jennings, J. R., Manuck, S. B., & Gianaros, P. J. (2017). Omega-3 Supplementation and the Neural Correlates of Negative Affect and Impulsivity: A Double-Blind, Randomized, Placebo-Controlled Trial in Midlife Adults. Psychosomatic Medicine, 79(5), 549–556. https://doi.org/10.1097/PSY.0000000000000453

Hu, F. B., Bronner, L., Willett, W. C., Stampfer, M. J., Rexrode, K. M., Albert, C. M., Hunter, D., & Manson, J. E. (2002). Fish and omega-3 fatty acid intake and risk of coronary heart disease in women. JAMA, 287(14), 1815–1821. https://doi.org/10.1001/jama.287.14.1815

Kiecolt-Glaser, J. K., Belury, M. A., Andridge, R., Malarkey, W. B., & Glaser, R. (2011). Omega-3 Supplementation Lowers Inflammation and Anxiety in Medical Students: A Randomized Controlled Trial. Brain, Behavior, and Immunity, 25(8), 1725. https://doi.org/10.1016/j.bbi.2011.07.229

Lane, K. E., Wilson, M., Hellon, T. G., & Davies, I. G. (2022). Bioavailability and conversion of plant based sources of omega-3 fatty acids – a scoping review to update supplementation options for vegetarians and vegans. Critical Reviews in Food Science and Nutrition, 62(18), 4982–4997. https://doi.org/10.1080/10408398.2021.1880364

Mazereeuw, G., Herrmann, N., Andreazza, A. C., Scola, G., Ma, D. W. L., Oh, P. I., & Lanctôt, K. L. (2017). Oxidative stress predicts depressive symptom changes with omega-3 fatty acid treatment in coronary artery disease patients. Brain, Behavior, and Immunity, 60, 136–141. https://doi.org/10.1016/j.bbi.2016.10.005

Raji, C. A., Erickson, K. I., Lopez, O. L., Kuller, L. H., Gach, H. M., Thompson, P. M., Riverol, M., & Becker, J. T. (2014). Regular fish consumption and age-related brain gray matter loss. American Journal of Preventive Medicine, 47(4), 444–451. https://doi.org/10.1016/j.amepre.2014.05.037

Streppel, M. T., Ocké, M. C., Boshuizen, H. C., Kok, F. J., & Kromhout, D. (2008). Long-term fish consumption and n-3 fatty acid intake in relation to (sudden) coronary heart disease death: The Zutphen study. European Heart Journal, 29(16), 2024–2030. https://doi.org/10.1093/eurheartj/ehn294

Takezaki, T., Inoue, M., Kataoka, H., Ikeda, S., Yoshida, M., Ohashi, Y., Tajima, K., & Tominaga, S. (2003). Diet and lung cancer risk from a 14-year population-based prospective study in Japan: With special reference to fish consumption. Nutrition and Cancer, 45(2), 160–167. https://doi.org/10.1207/S15327914NC4502_04

Terry, P., Lichtenstein, P., Feychting, M., Ahlbom, A., & Wolk, A. (2001). Fatty fish consumption and risk of prostate cancer. Lancet (London, England), 357(9270), 1764–1766. https://doi.org/10.1016/S0140-6736(00)04889-3

Back to blog