Within the fishing industry, there are two environments in which fish live: their natural environment or fish farms created by humans. Where we live and what we eat affects our health, and that also goes for the fish we consume. But studies show that health benefits from fish grown in fish farms have decreased over time.
A study from the University of Stirling in Scotland revealed that levels of omega-3s in farmed fish have decreased by 50 percent between 2009 and 2016—and this decrease has remained consistent since then.
Cut in half
The research was led by Professor Douglas Tocher, who stated in 2016, “About five years ago, a portion of Atlantic salmon of 130g was able to deliver three-and-a-half grams of beneficial omega-3. Now, the level of omega-3 has halved.”
Despite this, the analysis shows that of all the fish species currently produced by aquaculture, farmed salmon is still one of the richest sources of these fatty acids. The fish farming industry is exploring new ways to reverse this decline, which, according to the study, appears to be due to the type of feed given to farmed fish.
Omega-3 fatty acids play vital roles in many fundamental processes in the body. Many experts suggest one to two grams of total omega-3s per day in order to support optimal health.
Professor Tocher stressed that farmed salmon is still one of the richest sources of beneficial fish oils, and he urged people who buy farmed salmon for its potential health benefits to continue doing so. He also stated he was concerned about what could happen to omega-3 levels in a few years’ time: “If nothing [is] done, the level of the beneficial omega-3 can only really go down.”
Doubling your portions
Another researcher, Dr. Matthew Sprague, encourages the government to consider changing its advice to consumers. “At the moment, they are advising to eat two portions of fish per week—one of which should be oily,” he said. “But the advice of one portion of oily fish really should now be two portions at least.”
In response to the results, Dr. Alison Tedstone, chief nutritionist at Public Health England, said, “Ultimately, we all need to eat more oily fish; on average adults only consume 54g of oily fish per week, when official advice is to eat at least 140g. Our independent experts keep abreast of the evidence base to ensure advice remains up to date.”
Omega-3 levels in farmed salmon have dropped because of the industry’s success, which is struggling to keep up with the exponential growth of the human population. The farmed salmon get their omega-3s from smaller oily fish such as anchovies, which have been ground up and added to their feed. The oilier the fish that goes into the feed, the more omega-3s the salmon contains. Not long ago, 80 percent of the feed was made of oily fish—now, it’s more like 20 percent. The decline is a result of a cut to the amount of anchovies used in feed because, previously, it was recognized that far too many anchovies were being caught for fish food.
There has also been a growing demand for farmed salmon across the world. According to Dr. Paul Morris of Marine Harvest—one of the world’s largest producers of farmed salmon—this means a much-reduced supply of fish oil for feed has been spread ever thinner.
“We have a fixed amount of fish oil, and we are making sure that we are using that as efficiently as possible,” said Dr. Morris. “That won’t get us further than a certain amount of the way, so ultimately, we will have to look at other sources of (beneficial) omega-3 fatty acids.”
Looking for a solution
Farmed salmon have had very high levels of omega-3 in the past because of the easy availability of fish oil and fish meal. According to Dr. Morris, that has given the industry breathing space in order to find a solution. One such solution the industry is looking at is producing fish oils using marine algae, a replication of how it’s produced in the sea. But this process is currently uneconomical to reproduce in factories.
Another possibility is to grow seed oil plants that have been genetically modified to produce higher amounts of omega-3 fatty acids and add this material to fish food. Of course, it’s unknown to what extent consumers will accept genetically modified, plant-derived omega-3s and other nutrients.
Due to this decline in omega-3 levels in farm-raised fish, it’s likely more important than ever to supplement the diet with omega-3 fatty acids. Omega-3 fatty acids play a critical role in cardiovascular, brain, eye, and joint health and optimize the way the body regulates inflammation.
Regardless of your activity level, omega-3s are essential to your health. Our fish oils—or, as we like to call them, Nature’s Marine Superfoods—are made using only wild-caught Alaskan cod and salmon and retain all of the beneficial nutrients the fish have to offer. Be sure to read more on the difference between frozen and fresh fish and the health benefits of our fish oils.