Farmed Atlantic salmon has become a global favorite, praised for its flavor, versatility, and rich source of omega-3 fatty acids. However, recent research reveals a concerning trend—the omega-3 content in salmon has declined significantly over the years. This article explores why today’s farmed salmon contains less omega-3, the sustainability challenges of the aquaculture industry, and the innovative solutions emerging to address these issues.
📉 Why Omega-3 Levels in Farmed Salmon Are Dropping
Omega-3 fatty acids—especially the long-chain types like EPA and DHA—are essential for brain development, cognitive function, and overall heart health. In farmed salmon, these beneficial fats don’t naturally occur—they come directly from the fish’s feed.
Traditionally, this feed includes marine ingredients such as fishmeal and fish oil, made from wild fish like anchovies and trimmings from seafood processing. However, the global supply of these marine resources has been stretched thin since the 1990s, pushing the industry toward plant-based alternatives.
➡️ The problem? Plant oils don’t contain long-chain omega-3s.
📉 Between 2006 and 2015, the omega-3 content in a standard portion of salmon dropped by over 50%.
🌱 The Shift from Marine Ingredients to Plant-Based Feeds
To reduce costs and pressure on wild fish stocks, salmon farms have increasingly replaced fish oil with plant-based oils. While this may support sustainability in some areas, it has reduced the nutritional quality of the final product.
Yet, marketing still promotes farmed salmon as a reliable omega-3 source. For instance, two weekly portions of Scottish farmed salmon are enough to meet adult omega-3 needs, but only just—meaning further nutritional declines could soon undermine this claim.
♻️ Making Aquaculture More Efficient with Byproducts
To maintain omega-3 levels while reducing pressure on wild fish stocks, the seafood industry is turning toward a more circular economy model—maximizing the use of fish byproducts like skins, heads, and trimmings. These byproducts are rich in omega-3s and can be processed into fish oil and meal.
🔍 Current estimates suggest that around 50% of global fish oil now comes from such byproducts.
💸 With fish oil prices soaring to over $8,000 per ton in 2024, there’s also a strong economic incentive to recover these valuable materials.
Still, challenges remain:
- Byproducts are highly perishable
- Storage and transport, especially at sea, can be costly
- Much of the waste still ends up discarded
🧮 New Metric: nFifo for Omega-3 Tracking
A major innovation in sustainable aquaculture is the introduction of the nutrient Fish In Fish Out ratio (nFifo). Unlike traditional Fifo metrics, which only measure how much fish feed is used to produce farmed fish, nFifo tracks how much omega-3 from wild fish ends up in the salmon you eat.
✅ nFifo rewards feeds made from byproducts, encouraging sustainability
✅ Example:
- Current salmon feed with 20–25% marine ingredients → nFifo of 2.17
- Using only byproduct-sourced marine ingredients → nFifo drops below 0.5, with no loss in omega-3 content for the consumer
🌍 Balancing Nutrition and Environmental Impact
Marine ingredients may raise sustainability concerns, but they often have lower carbon, land, and water footprints compared to plant-based alternatives. The nFifo approach offers a nuanced perspective, helping both producers and consumers evaluate trade-offs in aquaculture feed choices.
The Blue Food Performance website now offers a tool to calculate nFifo, making it easier for certification bodies like the Aquaculture Stewardship Council and Best Aquaculture Practices to assess and adopt more sustainable standards.
🐟 What This Means for the Future of Farmed Seafood
If the seafood industry wants to remain both nutritionally beneficial and environmentally responsible, it must adopt more efficient, circular, and data-driven practices. Tools like nFifo could revolutionize how we evaluate fish feed sustainability—not only for salmon but potentially for all farmed fish species.
Consumers, too, will benefit from greater transparency, enabling smarter choices about the fish on their plates.
Conclusion:
The decline of omega-3 in farmed salmon is a warning signal—but also an opportunity. Through better use of byproducts and smarter metrics like nFifo, the aquaculture industry can create healthier fish and a more sustainable planet.