Why is it healthy to eat salmon?

Everything about the health benefits of eating salmon

Fatty fish like salmon that live in cold water, are one of the best marine sources of the omega-3 fatty acids Eicosapentaenoic acid (EPA) and Docosahexaenoic acid (DHA). These long-chain, flexible fatty acids play a number of important roles in the human body. Fatty acids are essential for foetal brain and visual development and healthy aging (1). The human body is not able to naturally produce sufficient amounts of EPA and DHA, and so it’s important that we obtain them through our diets (1).

Fat is an important structural component in our bodies and typically makes up around 50-60% of our brain mass (2). It's especially important for expectant mothers and children to consume sufficient amounts of EPA and DHA in their diet, to ensure adequate growth and development of the brain. A study by RKBU Vest Uni Research and Institute Of Marine Research showed that the consumption of fatty fish like salmon had a positive influence on the cognitive skills and the memory of children (3). The same applies to the elderly, who, over time, will show a decrease in DHA levels in their brain, with potential cognitive consequences if intake is not maintained.

DHA makes up 90% of the omega-3 fatty acids in the brain and is mainly found in the gray matter. Gray matter is responsible for processing information and memory function. DHA is thus important for our ability to concentrate, plan and problem-solve, as well as for our social, emotional and behavioral development. DHA plays an important role in communication processes between nerve cells, while EPA is important for the transport of oxygen and glucose in the blood, further supporting brain activity (4).

EPA and DHA are known to be important in regulating blood pressure, decreasing triglyceride-levels in the blood and in promoting vascular health. High levels of triglycerides can lead to cardiovascular disease and increased likelihood of stroke or myocardial infarction. Patients with abnormally elevated triglyceride levels may often receive EPA and DHA supplements as a treatment (5).

The fatty acids also play an important role in the immune system. When inflammation occurs, Cyclooxygenase (COX) enzymes react with EPA, DHA, and Arachidonic acid (AA), and oxidize into signal molecules (6). These molecules play important roles in our inflammatory response to inflammation and wounds. Prostaglandin E2 (PG E2) is made from omega-6 fatty chains such as AA which are found naturally in plants and animal food products (7). PG E2 contributes to stopping bleeding and healing wounds. However, since elevated levels of PG E2 can lead to blood clots and chronic inflammation, it’s important that PG E2 is regulated by Prostaglandin E3 (PG E3), which is made in the body from the oxidized EPA. PG E3 made from these fatty acids, has an anticoagulating effect on blood plates, and also has beneficial anti-inflammatory properties (7). Omega-3 fatty acids are important in regulating the content of PG E2, and in interaction, these signal molecules promote the immune system.

A significant decrease has occurred in the content of marine ingredients in farmed salmon feed over the last 50 years. In 2022, farmed salmon typically receive fish feed with marine content of around 30%. The Norwegian Food Research Institute (Nofima) published a scientific report in 2016 that researched the long-term effects on salmon of a diet with lower concentrations of omega-3 fatty acids (8). There was an observed correlation between feed with a low content of omega-3 and higher salmon mortality, infections, viruses, and inflammation. Lower omega-3 content also correlated with lower content of EPA and DHA in salmon muscle tissue, and an increased amount of fat in their liver and around their intestines (9). Marine feed ingredients clearly have a direct impact on fish welfare as well as on the nutritional value of the final food product (9). That’s why Pure Norwegian Seafood feeds their salmon a diet that has up to 70% marine ingredients and thus higher than average levels of bioavailable omega-3 fatty acids. As a result, Pure Norwegian Seafood experiences lower salmon mortality and rates of illnesses and ensures, a high content of omega-3 in their salmon. Pure Norwegian Seafood is leading an interdisciplinary science project in cooperation with Møreforskning Research Institute, the Akerblå Group and the Norwegian National Technical University (NTNU) to study the correlation between the quality of feed and fish welfare (10).

In addition to beneficial fatty acids, salmon is also rich in vitamin D, iodine, selenium, and vitamin B-12. Vitamin D helps in the adsorption of calcium, which strengthens our bones. For Norwegians, it's especially important to get enough vitamin D because during the winter we experience low exposure to sunlight, an important source of vitamin D. Iodine is particularly important for pregnant women because it contributes to the development of the foetal brain. It also plays a role in hormone production as well as in general metabolic functioning. Selenium also contributes to the upholding functioning of the immune system while Vitamin B-12 is involved in the production of cellular DNA, as well as in helping efficient blood circulation through the human body (11).

The Norwegian Directorate of Health recommends that everybody eat 300-450 grams of fish each week. At least 200 grams of this should be from fatty fish like salmon, trout, mackerel, or herring. It's recommended that we eat at least 2-3 dinners containing fish each week, and salmon is a healthy source of protein, especially if it replaces the protein we would otherwise get from red and processed meats (12).

The Norwegian Scientific Committee for Food and Environment (VKM) was asked by the Norwegian Food Safety Authority to carry out risk and benefit analysis of fish consumption in Norwegian diets using available empirical data and research. The VKM concluded that it is well documented that fish consumption helps protect against cardiovascular diseases and promotes heart health, and that it makes a positive contribution to the development of the foetal and infant nervous systems. They also came to the conclusion that farmed salmon contains sufficiently low amounts of environmental toxins that they are considered as completely safe to consume in any quantity. They thus concluded that prior advice to reproductive age women and to pre-pubescent girls that they should limit their intake of fatty fish like salmon for health reasons no longer applies (13). Regardless, Pure Norwegian Seafood samples and analyzes their salmon continuously; to ensure that no recommended limits of any regulated substances are exceeded and they never use genetically modified organisms (GMO) in their feed as this is forbidden in Norway. For this and many other reasons, Pure Norwegian salmon is an important building block for your good health. So, take care of your body by eating salmon throughout your life.

1. Swanson, D., Block, R., & Mousa, S. A. (2012). Omega-3 fatty acids EPA and DHA: health benefits throughout life. Advances in nutrition (Bethesda, Md.), 3(1), 1–7. https://doi.org/10.3945/an.111... Available at: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3262608/
2. De Lorgeril, M., et al. (1999). Mediterrranean diet, traditional risk factors, and the rate of cardiovascular complications after myocradical infarction: final report of the Lyon Diet Heart study. Circualtion., p. 779-785. Available at: https://www.pileje.com/health-information/specific-role-dha-epa-type-omega-3-fatty-acids
3. Nagelsen, V. (2018). Barn løste oppgaver bedre med mer omega-3: Havforskningsinstituttet Tilgjengelig fra: https://forskning.no/barn-og-ungdom-mat-og-helse-partner/barn-loste-oppgaver-bedre-med-mer-omega-3/1189362
4. Schmoe, J. (U.D). The best fat for your brain: DHA in fish and algae oil. The Functional Neurology Center: Available at https://thefnc.com/research/the-best-fat-for-your-brain-dha-in-fish-and-algae-oil/
5. Miller M, Stone NJ, Ballantyne C, Bittner V, Criqui MH, Ginsberg HN Et al., (2019) Triglycerides and Cardiovascular Disease. American Heart Association. doi:10.1161/CIR.0b013e3182160726 Available at: https://www.ahajournals.org/doi/10.1161/CIR.0000000000000709
6. Calder, P.C. (2013) Omega-3 polyunsaturated fatty acids and inflammatory processes: nutrition or pharmacology? Br J Clin Pharmacol. doi: 10.1111/j.1365-2125.2012.04374.x. Available at: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3575932/
7. Cherian, G. (2013) Bioactive Food as Dietary Interventions for Liver and Gastrointestinal Disease. Oregon State University. Available at: https://www.sciencedirect.com/topics/agricultural-and-biological-sciences/prostaglandin-e3
   
8. Ruyter, B. Mira, B. Bæverfjord, M. Østbye, G. K, T. Ytrestøyl Et al., (2016) Langtidseffekter av lave omega-3 nivåer i fôr på laksens helse, Nofima. Tilgjengelig her: https://nofima.no/publikasjon/1363723/
9. Aas, T,S. Ytterstøyl, T. Åsgård, T. (2019) Utilization of feed resources in the production of Atlantic salmon (salmo salar) in Norway: An update for 2016, Nofima. Available at: https://nofima.brage.unit.no/nofima-xmlui/bitstream/handle/11250/2637123/1-s2.0-S235251341930256X-main.pdf?sequence=1&isAllowed=y
10. [10] (2020) Skal forske på hjertehelsa hos laks. Møreforskning, Møreforskning. Tilgjengelig her: https://www.moreforsk.no/om-oss/nyheter/marin/skal-forske-pa-hjertehelsa-hos-oppdrettslaks/680/3460/
11. Dahl, L. Bjørkkjær, T. Graff, I. Malde, M. Klementsen, B. (2006) Fisk – ikke bare omega-3. Tidsskr Nor Lægeforen 2006, Tilgjengelig her:
    https://tidsskriftet.no/2006/01/oversiktsartikkel/fisk-ikke-bare-omega-3
12. Helsedirektoratet (2016). 5. Fisk til middag to til tre ganger i uken. Oslo: Helsedirektoratet (sist faglig oppdatert 24. oktober 2016, lest 11.november 2022). Tilgjengelig her: https://www.helsedirektoratet.no/faglige-rad/kostradene-og-naeringsstoffer/kostrad-for-befolkningen/fisk-til-middag-to-til-tre-ganger-i-uken
13. VKM (2014). Benefit-risk assessment of fish and fish products in the Norwegian diet – an update. Scientific Opinion of the Scientific Steering Committee. VKM Report 15 [293 pp], ISBN: 978-82-8259-159-1, Oslo, Norway. Available at: https://vkm.no/risikovurderinger/allevurderinger/nytteogrisikovurderingavfiskinorskkostholdenoppdateringavvkmsrapportfra2006basertpanykunnskap.4.2994e95b15cc54507161df4e.html