Quantcast

Wild vs. Farmed Salmon: Can Some Fish Be Bad For You?

Food

Salmon is commonly prized for its health benefits.

It is a fatty fish that is loaded with Omega-3 fatty acids, which most people don’t get enough of.

However … not all salmon is created equal, unfortunately.

Today, a lot of the salmon we eat isn’t caught in caught in the wild, but bred in fish farms.

Salmon-farming shouldn’t be done at the expense of wild salmon.
Photo credit: Shutterstock

The Difference Between Wild and Farmed Salmon

Wild salmon is caught in the wild, in its natural environment … oceans, rivers and lakes.

But half of the salmon sold worldwide comes from so-called fish farms, also known as aquacultures.

The annual global production of farmed salmon has increased from 27,000 to more than 1 million metric tons in the past two decades.

Whereas wild salmon eats other organisms found in its natural environment, farmed salmon is given a processed high-fat feed in order to produce larger fish.

Wild salmon is still available, but global stocks have halved in just a few decades.

Bottom Line: The production of farmed salmon has increased dramatically in the past two decades. Farmed salmon has a completely different diet and environment than wild salmon.

There Are Some Important Differences in Nutrition Composition

To the left, you see the nutrient composition of a half fillet (198 grams) of wild salmon. To the right, you see the numbers for farmed salmon.

As you can see in the table, nutritional differences between wild and farmed salmon can be pretty significant.

Farmed salmon is much higher in fat … it contains slightly more Omega-3s, much more Omega-6 fatty acids and three times the amount of saturated fat. It also contains 46 percent more calories, mostly from fat.

Read page 1

Farmed salmon also contains some Vitamin C, which is added to the feed.

Conversely, wild salmon is higher in minerals, including potassium, zinc and iron.

Bottom Line: Wild salmon contains more minerals. Farmed salmon is higher in Vitamin C, saturated fat, polyunsaturated fatty acids and calories.

Difference in Polyunsaturated Fat Content

There are two main types of polyunsaturated fats … Omega-3 and Omega-6 fatty acids.

These fatty acids have important roles to play in the human body.

We need both in the diet, otherwise we end up sick. That’s why they are termed the “essential” fatty acids (EFAs).

However … we need to get these fatty acids in a certain balance.

Most people today are eating too much Omega-6, and the delicate balance between these two types of fatty acids is heavily distorted towards Omega-6.

Many scientists have speculated that this can drive increased inflammation and may play a role in the pandemics of chronic diseases like heart disease and others.

Here’s where it gets interesting … farmed salmon has three times the total fat of wild salmon, but a large part of these fats are Omega-6 fatty acids.

For this reason, the Omega-6:Omega-3 ratio is about three times higher in farmed salmon, compared to wild.

However … I don’t really think this is a cause for concern. Even though farmed salmon contains Omega-6, the O6:O3 ratio is still excellent (at 1:3-4), it’s just less excellent than that in wild salmon, which is at 1:10.

Salmon, both farmed and wild, should lead to a massive improvement in Omega-3 intake for most people, and is often recommended for that purpose.

In a four week study of 19 volunteers, eating farmed Atlantic salmon twice per week increased DHA (an important Omega-3 fatty acid) levels in the blood by 50 percent.

Bottom Line: Farmed salmon is much higher in Omega-6 fatty acids than wild salmon, but the amount is still too low to be a cause for concern.

Wild salmon is still available, but global stocks have halved in just a few decades.

Farmed Salmon is Much Higher in Contaminants

Fish tend to accumulate potentially harmful contaminants from their environment.

These contaminants are found in the water they swim in, as well as the foods they eat.

Read page 1

But farmed salmon has much higher concentrations of contaminants than wild salmon.

European farms have more contaminants than American farms, but species from Chile seem to have the least.

Some of these contaminants include polychlorinated biphenyls (PCBs), dioxins, and several chlorinated pesticides.

Arguably the most dangerous pollutant found in salmon is the PCBs, which are strongly associated with cancer and various other health problems.

One study investigated more than 700 salmon samples from around the world and found that on average, the PCB concentrations in farmed salmon were eight times higher than in wild salmon.

Those contamination levels are deemed safe by the FDA but not by the U.S. Environmental Protection Agency (EPA).

Researchers suggest that if the EPA guidelines were applied to the farmed salmon they tested, recommendations would be to restrict salmon to no more than once per month.

However, many argue that the benefits of consuming Omega-3s from salmon outweigh the health risks of contaminants, which is a reasonable assumption.

While it is hard to say for sure, we know that risks are far fewer if you eat wild salmon instead of farmed.

Bottom Line: Farmed salmon contains much higher amounts of contaminants like PCBs, but the amount varies between fish from different regions.

Mercury and Other Trace Metals in Salmon

The current evidence for trace metals in salmon is conflicting.

Two studies found very little difference in mercury between wild and farmed salmon.

However, one study found that wild salmon had levels three times higher.

Levels of arsenic have been found to be higher in farmed salmon, but levels of cobalt, copper and cadmium higher in wild salmon.

In any case, trace metals in either variety of salmon are found in such low amounts that they do not appear to be a cause for concern.

Bottom Line: For the average person, trace metals in salmon do not appear to be found in harmful quantities. This goes for both farmed or wild salmon.

Is Wild Salmon Worth the Extra Cost and Inconvenience?

It is important to keep in mind that farmed salmon is still very healthy.

Farmed salmon tends to be much larger and contains higher amounts of Omega-3s.

Wild salmon is also much more expensive than farmed and may not be worth the extra cost for some people. Depending on a few things, it may be inconvenient (or impossible) for you to access wild salmon.

However, because of the dietary differences, farmed salmon also contains much more potentially harmful contaminants than wild salmon.

While these contaminants appear to be safe for the average person consuming moderate amounts, some experts have recommended that children and pregnant women only eat wild-caught salmon … just to be on the safe side.

Salmon is Healthy, no Matter Which Way You Slice it

It is a good idea to eat fatty fish such as salmon once or twice a week for optimal health.

It also happens to be loaded with other beneficial nutrients, is highly satiating (and therefore weight loss friendly), not to mention incredibly delicious.

The only real concern with farmed salmon is organic pollutants like PCBs. If this is something you’re concerned about, then do some research on the origins of your salmon and choose one that wasn’t bred in polluted waters.

Given the high amount of Omega-3s, quality protein and beneficial nutrients, I believe that the benefits of eating salmon (whether farmed or wild) far outweigh the negatives for most people.

I personally eat farmed salmon every week, and I am not at all concerned about it. I would choose wild if I could, but unfortunately it is not available to me right now.

If wild salmon is easily accessible to you, then that’s a better option. But farmed salmon is still healthy … just slightly “less healthy” than wild salmon.

YOU ALSO MIGHT LIKE

25 Vegan Sources of Calcium

Move Over, Quinoa, a New Superfood Grain Is in Town

6 Reasons to Eat an Avocado

EcoWatch Daily Newsletter

California Condor at soaring at the Grand Canyon. Pavliha / iStock / Getty Images

North America's largest bird passed an important milestone this spring when the 1,000th California condor chick hatched since recovery efforts began, NPR reported Sunday.

Read More Show Less
The Roloway monkey has been pushed closer to extinction. Sonja Wolters / WAPCA / IUCN

The statistics around threatened species are looking grim. A new report by the International Union for Conservation of Nature (IUCN) has added more than 9,000 new additions to its Red List of threatened species, pushing the total number of species on the list to more than 105,000 for the first time, according to the Guardian.

Read More Show Less
Sponsored
Golde Wallingford submitted this photo of "Pure Joy" to EcoWatch's first photo contest. Golde Wallingford

EcoWatch is pleased to announce our third photo contest!

Read More Show Less
BRENDAN SMIALOWSKI / AFP / Getty Images

The campaign to re-elect President Donald Trump has found a new way to troll liberals and sea turtles.

Read More Show Less
Night long exposure photograph of wildifires in Santa Clarita, California. FrozenShutter / E+ / Getty Images

By Kristy Dahl

Last week, UCS released Killer Heat, a report analyzing how the frequency of days with a dangerously hot heat index — the combination of temperature and humidity the National Weather Service calls the "feels like" temperature — will change in response to the global emissions choices we make in the coming decades.

Read More Show Less
Sponsored
A Zara store in Times Square, Causeway Bay, Hong Kong. Timahaowemi / CC BY-SA 3.0

Green is the new black at Zara.

The Spanish fast fashion behemoth has made a bold move to steer its industry to a more environmentally friendly future for textiles. Inditex, Zara's parent company, announced that all the polyester, cotton and linen it uses will be sustainably produced by 2025, as CNN reported.

Read More Show Less
Pexels

By Gavin Van De Walle, MS, RD

Whether you enjoy running recreationally, competitively, or as part of your overall wellness goals, it's a great way to improve your heart health.

Read More Show Less
Text from the plaque that will mark the site where Ok glacier once was. Rice University

By Andrea Germanos

A climate change victim in Iceland is set to be memorialized with a monument that underscores the urgent crisis.

Read More Show Less