Farmed raised Atlantic Salmon has been scrutinized for decades. The public needs an accurate update. Here, we discuss the nutrition, sustainability, and safety of farmed Atlantic Salmon according to the most recent scientific data.
Highlights
Nutrition: Farmed salmon is one of the best sources of protein and omega-3s. With the adoption of more sustainable feeds around 2009, the omega-3 content has decreased in the past decade. But even with this shift, farmed salmon remains one of the best providers of this non-negotiable nutrient.
Sustainability: Salmon farming is becoming more sustainable through innovations and better management. Farmers are working with scientists and engineers to eliminate escapes, minimize pollution, and decrease reliance on marine proteins for feed.
Safety: While contaminants in farmed salmon were a big concern in the early 2000s, they have decreased to negligible amounts over the last two decades. Innovations around disease prevention are improving the biological and economic health of salmon farming.
Why write about farmed salmon in 2022?
The public needs an accurate update. Articles written as recently as February 2022 have discouraged frequent consumption of farmed salmon due to its “high contaminant levels.” What were these claims based on? Research from 2003.
Science, technology, and regulations have improved since then.
Here, we aim to discuss the nutrition, sustainability, and safety of farmed salmon based on the most recent, peer-reviewed science. It’s 2022, and it’s time to update the paradigm around farm raised Atlantic Salmon.
Background: Salmon farming began in the 1960’s.
Modern salmon farming, also known as salmon aquaculture, began in Norway in the 1960’s. In the following decades, Canada, Chile, Scotland, and the U.S. also began farming salmon on a commercial scale. Today, salmon farming is the fastest growing protein production system in the world, and it produces over 75% of the salmon consumed worldwide.
What species of salmon are farmed?
90% of salmon aquaculture produces Atlantic Salmon because of its quick growth rate and resistance to disease. The other 10% of salmon aquaculture produces Coho Salmon, Chinook Salmon, and Salmon Trout.
Nutrition: Farmed salmon is very nutritious–just a little less than before.
A 3.5 oz. farm raised Atlantic Salmon fillet (roughly the size of a checkbook) contains the following nutrients:
- 17g of protein
- 855 mg of EPA omega-3
- 1000 mg of DHA omega-3
The health benefits of EPA and DHA omega-3s are indicated in many peer-reviewed scientific studies as guardians of heart health, cognitive performance, and emotional well-being. These non-negotiable nutrients are found naturally only in cold-water fish like Atlantic Salmon. However, the needed push for sustainability in farmed salmon feeds has led to a decrease in omega-3 levels.
The Push for Sustainable Feeds
In 2016, Nature published a scientific report titled “Impact of sustainable feeds on omega-3 long-chain fatty acid levels in farmed Atlantic salmon, 2006–2015.” The report discusses how, around 2009, feed manufacturers were using less marine protein–fish oil and fishmeal–and more terrestrial plants as ingredients. This shift has surely increased the sustainability of salmon farming, making it less reliant on other fish as an input, but it has been coupled with nutritional compromise: less omega-3 and more omega-6 in the final product.
We don’t see this as a reason to sideline farmed salmon. One portion of farmed Atlantic Salmon still contains more than half of the weekly requirement of 2500 mg combined EPA and DHA. While the omega-6 to omega-3 ratio is not as good (low) as before, it’s still favorable. Farmed salmon has an omega-6 to omega-3 ratio of 1:4 according to Nature’s report—much better than that other meat sources like beef, which has a ratio of 26:1.
From a public health standpoint, farmed Atlantic Salmon will continue to be key in providing the world with omega-3s. Today, for every human on Earth to satisfy their daily EPA & DHA omega-3 requirement, we need to be producing 1.25 metric tons per year—currently, we only produce .8. As one of the best sources of EPA and DHA omega-3s, salmon farming is a hero in this regard, and innovations to improve it’s outcomes should be well supported.
The Nutrition of Farm Raised vs Wild Caught Salmon
The 2016 review by Nature made the following conclusions about the nutritional content of wild vs. farm raised salmon: “despite the reduction in EPA and DHA levels due to the increased use of plant ingredients in salmon feeds, farmed Atlantic salmon still provide a significantly higher amount of EPA + DHA than wild salmon.” However, wild salmon contains less omega-6s and higher levels of other vitamins and minerals due to its diverse natural diet. Innovations to further improve the nutritional outcomes of farmed salmon are underway.
How are farms improving the nutrition of farmed salmon in 2022?
Aquaculture scientists, feed manufacturers, and salmon farmers are unified in solving the problem of making salmon feeds more sustainable while preserving nutritional content. We have listed some current innovation projects below.
- experimenting with krill, micro-algae, and other EPA & DHA-rich, non-fish ingredients
- engineering feeds to allow salmon to absorb more omega-3s
- engineering feeds to help salmon convert the form of omega-3 found in plants—ALA—into the beneficial EPA and DHA forms
- breeding for salmon that absorb higher levels of EPA & DHA omega-3s from feeds
Sustainability: Farmed salmon had great start, and it’s only getting better.
Salmon Farming is Inherently Sustainable
Fish farming is carbon-light.
As demand for protein continues to rise, the world will need to move towards more efficient forms of protein production. While it’s not perfect, aquaculture presents a hopeful solution. According to a 2020 scientific report by Nature, aquaculture only contributed to .49% of greenhouse gas emissions in 2017. For comparison, we’ve included a graph that plots the greenhouse gas emissions for common proteins we consume by Our World In Data.
Farmed Salmon Doesn’t Use Much Land and Water
Today, the ocean covers 71% of the Earth’s surface. With a growing population and limited land, the ocean holds massive potential for nutritional and economic prosperity. A 2017 report from UC Santa Barbara suggests that if we were to utilize just .15% of the ocean for aquaculture, we would meet the world’s growing demand for seafood. To be clear, we do not see aquaculture eliminating wild-catch fisheries, rather, we see sustainable fisheries and aquaculture growing together to supply protein, nutrients, and economic prosperity to the world.
Salmon farming still requires land, especially with more terrestrial proteins being used for feeds. But feed scientists are experimenting with less land-heavy ingredients like microalgae and insects, all without seeing significant decreases in salmon quality.
Farmed Salmon is Becoming More Sustainable
Pollution is a Problem Being Solved
Byproducts of salmon farms, like fecal matter and uneaten feed, can damage local environments. To combat this, manufacturers are making feeds that are more environmentally friendly and biologically absorbable. To dilute the effect of the remaining byproducts, farms are being established in deeper waters with stronger currents, and existing farms are rotating farm plots after every harvest (Norwegian Seafood Council). In some places, regulations require a predictive model of how the farm will affect the surrounding environment before a license is even issued.
Eliminating Escapes
Under certain circumstances, farmed salmon can escape from ocean pens, mix with the native population, and dilute the local gene pool. This problem is being addressed through process, structural, and biological engineering.
- Process: farms are implementing smarter regulations around the high-risk stages of salmon rearing
- Structural: cages are being improved to eliminate escape
- Biological: farms are rearing sterilized salmon so that, in the case that they do escape, they will not negatively affect the fitness of wild fish
Sustainability Certifications in Aquaculture
Salmon farms that are making the effort to face sustainability challenges head on are recognized by certifications.
The Global Sustainable Seafood Initiative (GSSI) is an organization with over 90 stakeholders around the world, including the U.N.’s Food and Agriculture Organization. GSSI has recognized certification schemes as worldwide benchmarks for aquaculture sustainability. Look for these labels when choosing farmed salmon:
GLOBALG.A.P. covers the entire production chain from feed to fork, and to have a certified product, all the different parts of the value chain need to be GLOBALG.A.P. certified.
GlobalG.A.P. Website
Scrutinized criteria in salmon farming:
- Legal compliance
- Food safety
- Workers’ occupational health, safety and welfare
- Animal welfare
- Environmental and ecological care
The world’s leading certification and labelling programme for responsibly farmed seafood. ASC certifications require exceptional water quality, responsible sourcing of feed, disease prevention, animal welfare, the fair treatment and pay of workers and maintaining positive relationships with neighbouring communities.
ASC Website
An ASC certification covers the breadth of aquaculture production and beyond. For example, farms seeking an ASC certification are required to source all feed ingredients from sustainable mills and fisheries. ASC certified farms are also required report carbon emissions, measure mineral levels in their water, and adhere to strict fish health management plans.
Best Aquaculture Practices (BAP) is a seafood specific certification program that addresses the four key areas of sustainability—environmental, social, food safety, and animal health & welfare—at each step of the aquaculture production chain.
BAP Website
BAP uses a 4-star rating system to signify a farm’s level of sustainability. At Pucci Foods, we work with farms that have achieved a 4-star BAP certification in their farming production processes.
Safety: Farmed Atlantic Salmon in 2022 is Safe to Eat
Contaminants
Contaminants, like dioxins, PCBs, and metals, may be found in food that is produced near human activity. The burning of fossil fuels, discharge from industrial and household activity, and the improper disposal of waste all contribute to contaminants in the environment. In the ocean, bacteria convert contaminants into food for plankton, and plankton are eaten by fish. This is how contaminants get into seafood. Because significant consumption of these contaminants can lead to negative health outcomes, the EU, WHO, and FDA. all set tolerable daily intake (TDI) levels for these substances.
Early Contaminant Levels
This year, an article was published suggesting that people restrict farmed salmon consumption, claiming it has “high contaminant levels.” As with any claim like this, it is important to follow the link back to the scientific research it cites. In the case of this article, the authors travelled back in time to reference a study from 2003. Indeed, farmed salmon in the early 2000s did contain higher levels of contaminants. But it’s 2022.
In fact, we don’t even need to look at recent data to see that contaminants have decreased since 2003. Research published in Environment International in 2015 measured contaminant levels in Norwegian farmed salmon in the period from 1999-2011. Remember the push for more sustainable feeds around 2009? That not only improved sustainability, but also decreased contaminant levels. The researchers concluded the following:
Dioxins and dl-PCBs, sum DDT, As, and Hg had decreased during the last decade.
Stable levels were observed for PCB6 and quantifiable pesticides.
All measured contaminants were below the EU regulatory maximum limits.
Based on their data, the authors concluded that it was safe to eat 1.3kg of farmed salmon a week based on EU tolerable daily intake levels in 2011. In 2011, the average American only ate 6.8 kg of total seafood all year (see visual below). Farmed salmon was safe to eat in moderation from the early 2000s, and it’s been extremely safe to eat for the past decade. The next time someone asks you, “Is Norwegian farmed salmon safe?” You can point them to the Environment International article.
Farmed vs. Wild Salmon
The most recent article on contaminants in farmed vs wild salmon we could find was from 2017. The title of the article sums up the findings quite well: “Lower levels of Persistent Organic Pollutants, metals and the marine omega-3-fatty acid DHA in farmed compared to wild Atlantic salmon (Salmo salar).” (NOTE: the study measured DHA omega-3 fatty acids as a percentage of total fat content. Farmed salmon still contains more omega-3s due to its higher fat content overall.)
We see these two studies as strong evidence that farmed salmon in 2022 is safe to eat. As always, talk to your physician before making significant changes to your diet.
2022 U.S. Dietary Guidelines for Salmon
The USDA and works with Health and Human Services to publish Dietary Guidelines for Americans. The FDA refers to these guidelines in on their advisory page on eating fish. The only explicit limits on fish consumption are for those who are pregnant or breastfeeding and children under the age of 11.
Diseases
Just like cows or chickens, salmon is prone to disease on the farm. In the early days of salmon aquaculture, antibiotics were commonly used as a disease prevention protocol. Today, it has been eliminated in almost all countries. The countries that still use them face the problem of antimicrobial resistance, as documented in this study published in Frontiers in Microbiology.
To mitigate the negative effects of antimicrobial resistance, disease prevention has taken other forms, like breeding for disease resistant salmon, minimizing human contact with the salmon, adding probiotics and immune boosting nutrients to feeds, and the administration of vaccines. Vaccine content, administration, and washout periods are approved by the F.D.A. to ensure safe consumption of the final product.
Sea Lice
Sea lice are small crustaceans that feed on a host fish like salmon. While sea lice are not harmful to humans, they make farmed salmon unmarketable. The cost of sea lice on the salmon farming industry is estimated to be USD 400 million – 500 million per year (Seafood Source). Innovating around sea lice intervention is in the best interest of both farms and consumers. We have listed some current innovations here:
- diets that boost salmon immunity to sea lice
- dislodging lice with a low pressure spray
- having salmon swim through warm water to detach lice, a.k.a. thermal delousing
- releasing feeder fish into farms to consume sea lice
Source Salmon from the Best Farms
Sourcing your salmon from certified farms is the best way to ensure the highest levels of nutrition, sustainability, and safety. As a 100-year-old seafood distributor, Pucci Foods has implemented a supplier verification process that ensures our Atlantic Salmon is sourced from the best farms. We have listed some of our partner farms below.
MOWI is the largest supplier of farm-raised salmon in the world and was rated the #1 Sustainable Protein Producer in the world by the Coller FAIIR Protein Producer Index. A large part of MOWI’s sustainability regime is investing in an in-house R&D team focused solely on optimizing feeds.
A global organization of 3500 associates, Cermaq bases its policies on supporting the UN’s 17 Sustainable Development Goals. Cermaq runs farms in Canada, Chile, and Norway that are BAP and ASC certified.
Leroy is based in Norway, but it delivers 500000 meals to 80 countries every day. Its GlobalG.A.P. and ASC certified farms are a large part of their mission to improve health, slow climate change, and empower people.
Recirculating Aquaculture Systems (RAS)
Up to this point, we have been discussing salmon that is produced with open aquaculture systems. Open aquaculture systems are continuous with the surrounding environment like a salmon pen floating in the ocean. These systems are responsible for most of the farmed salmon produced around the world today because they require little land and fresh water. However, they present the risks of pollution, contaminants, and diseases mentioned above. Recirculating aquaculture systems have the potential to mitigate these risks.
Recirculating aquaculture systems, RAS, are closed systems, meaning they are not in direct contact with the surrounding environment. As the name suggests, water used in RAS is recirculated after filtration, sterilization, enrichment with nutrients, and de-acidification. This allows RAS to be built on land with little fresh water input. Recirculating systems are the subject of sustainable development conversations around the world for the following reasons:
- While not as carbon-light as open ocean aquaculture, they present a sustainable protein production solution
- They eliminate the risk of pollution and disease-transfer to the surrounding environment
- If managed well, they have the potential to eliminate disease, parasitic infections, and other contaminants in the salmon as shown by this study published in Aquacultural Engineering
- Waste from they can be collected and engineered into useful products, like biofuel
- they can be placed near consumers, eliminating carbon emissions from the transportation of products
A 2016 study published in Aquacultural Engineering found that, at scale, the cost of salmon produced with RAS is comparable to that of salmon produced in traditional open net pens. The study also found that, from the perspective of the U.S. consumer, the carbon footprint of salmon produced via domestic RAS is half of the carbon footprint of ocean farmed salmon overseas. However, the study also reported that the return on investment for RAS was also about half.
The Future of RAS
Just like any food production system, RAS has its challenges: it requires a large upfront investment, maintenance by highly trained personnel, and constant monitoring. More salmon RAS projects are required for innovation and research to improve the industry. We are excited to report that the number of RAS projects are increasing.
A 2019 report by Seafood Source showed that, between 2018 and 2019, the number of salmon RAS projects nearly doubled. The country with the highest proposed production volumes was the United States. These U.S.-based salmon RAS companies, like Bluehouse Salmon, eliminate the financial and environmental costs of transporting farmed salmon from overseas. Bluehouse Salmon and others are already recognized by seafood sustainability certifications and will continue to push the industry forward.
Farmed Salmon in 2022 is Nutritious, Sustainable, and Safe
In 2022, farmed salmon is nutritious, sustainable, and safe. As with every industry, salmon farming has its challenges, but supporting producers that are addressing these challenges funds the solutions. As the world demands more protein, and more people start eating fish at a younger age, aquaculture will continue to be a huge player in providing omega-3s and other key nutrients to more people.
The untapped potential of our oceans and the promise of RAS calls us to look to farmed salmon to nourish our bodies and provide economic prosperity. We are happy to support you in offering farmed salmon in your grocery stores and restaurants in 2022.
Pucci Foods is a 100 year old seafood distributor based in Hayward, California. We are known for going above and beyond for our customers in supplying quality seafood in a sustainable way. From fresh wild catch to affordable, sustainably farmed species, we are the seafood solution for restaurants, retailers, institutions, and wholesalers who are looking for fresh quality, committed care, and sustainable satisfaction.
