High in protein, high in omega-3 fatty acids, a provider of vitamin D, B12, niacin, selenium, B6, magnesium and calcium—those are just some of the benefits of eating salmon and other fatty fish.
But what about farmed salmon vs. wild salmon? Are there any differences?
The answer is a resounding yes. And these differences are significant for health.
For starters, North American, South American, and European farm-raised salmon have high levels of PCBs and other environmental toxins (as many as 14 toxins--some of them human carcinogens) than wild salmon, according to researchers at Indiana University and five additional research centers. The study’s leader, Professor Ronald Hites, from the IU School of Public and Environmental Affairs, said, “We think it’s important for people who eat salmon to know that farmed salmon have higher levels of toxins than wild salmon from the open ocean.”
They think it’s so important that they also recommended limitations on how much farmed salmon a person should eat per month. The recommended amounts varied from one-half a meal of salmon per month to no more than two meals of salmon per month. Compare those recommendations to how much wild salmon you can safely eat—which is as many as eight meals per month—and you catch a glimpse of how serious these scientists consider the toxins in farmed salmon.
And this is a rather broad problem, since the production of farmed salmon has increased 40-fold over the past twenty years. And it appears that the toxins may be derived from what these farm-raised salmon are fed. Hites and his fellow scientists measured toxins in this “salmon chow’—which is a mixture of ground-up fish and oil fed to the farm-raised salmon—and found a correlation between the toxicity of the feed and the toxicity of the salmon. They believe that the toxins are passed from the feed into the salmon.
But the toxin level in farmed salmon is not the only reason why wild salmon is preferred over farmed salmon. Here are some more convincing reasons:
Wild salmon contains more omega-3 fatty acids than farmed fish, a Norwegian study suggests. In the past, it was believed that farmed fish contained more beneficial omega-3s, but more recently, it is generally accepted that the percentage of omega-3 fats in farmed salmon is lower than in wild salmon. Additionally, farmed salmon is usually cooked in ways that reduce its fat content (due to its contaminants), thereby lowering its fatty acid content. Finally, fish feed is being used with less fish meat in it and more plant foods, which can lower the amount of omega-3s in the salmon.
Salmon farmers often use antibiotics and pesticides to control disease and these can be passed along to any consumer of the fish. These chemicals can potentially causes negative health effects for those who ingest the antibiotic-ridden or pesticide-laced salmon.
So, when it comes to your choice of salmon, it’s best to “take a walk on the wild side”—by selecting wild salmon, that is.