Health advisors say we need to eat more fish high in Omega 3 oils and salmon is one of those fish that we are supposed to consume more of. But when you get to the store there are tags that say 'farm raised' or 'wild caught' on the salmon. What do they mean and how do those differences impact you?
Farm Raised Salmon is Fattier
You would think that if we are supposed to be eating more omega-3 oils that fattier salmon would be a good thing, but it isn't in this case. Because they are fattier they do contain more omega-3 oils, but they also contain more omega-6 oils which are linked to inflammatory responses and increased chanced of diseases such as cancer.
Wild coho salmon have an omega-3 to omega-6 ratio of 15.3:1. In comparison farmed raised coho have a ratio of 3.1:1. The lower ratio means that the enzymes that convert these fats into the forms in which they are active in the body are more likely to be used up by the omega 6 fats.
Wild Salmon Have More Omega-3 Oils
Possibly because farm raised fish are fed a diet of processed food, which you can liken to feeding us fast food every day. Wild fish on the other hand are having to work their way through cold waters chasing fresh food every day. I suspect that this is key difference in the oil content between farmed and wild salmon.
Higher Pollutant Levels
Two studies-one in British Columbia and one in Great Britain are showing that farmed salmon accumulate more cancer-causing PCBs and toxic dioxins than wild salmon. There are several reasons for this but one key cause is the feed they are given.
Salmon chow contains fish oil-extracted from sardines, anchovies and other ground-up fish. Now while these are fish that salmon would normally eat, they are fed it in higher concentrations than they normally would get in the wild. These feed stock fish are accumulating their chemical loads from our waste and pollution and in turn it is making its way back to us.
To make matters worse most of these chemicals are fat soluble. This means that the fish with the most fat contain the most chemicals. As stated before, farmed fish are fattier than wild salmon, so in turn you are getting a bigger dose of cancer causing chemicals.
Farmed salmon from U.S. grocery stores was tested and was found to contain 16 times the PCBs found in wild salmon. Other studies done in Canada, Ireland and Britain have produced similar findings.
Pale Looking Salmon? They Can Fix That!
Because they are not swimming wild eating and don't get to absorb carotenoids from eating pink krill. Without treatment, farmed salmon would be pale and almost halibut looking.
To fix this pale meat problem, salmon farmers use a chemical called Canthaxanthin to color their fish's meat any color of pink that they want. There is even a color chart that they can pick from like you would find at the paint store!
Canthaxanthin is of course something you don't want to eat as it is linked to retinal damage called canthaxanthin retinopathy, which is the formation of yellow deposits on the eye's retina. we know this because it used to be found in tanning pills. Canthaxanthin has also been reported to cause liver injury and a severe itching condition called urticaria, according to the AAD.
Farmed Fish is Bad for the Enviroment
If the health reasons weren't enough reason to put you off eating farmed salmon, take some time to do some research on the environmental effects of salmon farms on our waters and on wild salmon. Personally I would like to see more work being done to protect out waters and promote wild grown salmon than farming them as we are today.
This isn't to say that farmed salmon doesn't have a future. Organic salmon farming is on the horizon. The proposed Galway Bay salmon farm is to be located a mile from any land mass in an area that has good currents to flush debris from the pens. Additionally the enclosures are much, much bigger than standard farms, improving the overall health of the fish and surrounding waters.
If the salmon farming communities move to facilities like this, then farmed salmon may become better to eat and better for you, but for now I will stick to my wild caught salmon.