4. Unsafe Contaminants
The FDA and EPA have both extensively studied mercury contamination in fish.
Wild salmon was consistently found to have a very low risk of causing mercury contamination in humans, even if eaten multiple times a day (14,15).
However, because farmed salmon is fattier, it can accumulate higher levels of fat-soluble toxins such as PCBs, a banned substance found in the carcinogen asbestos (16,17).
Farmed salmon live in overcrowded nets, making them a high risk environment for infection and parasites. These quickly spread throughout the net and can cause massive death and illness, meaning a huge loss of profit for farmers.
And so, these fish are exposed to large doses of antibiotics to ensure that they are healthy enough to be sold on the market (18).
Wild fish, on the other hand, aren’t exposed to humans or human-made substances until they are caught and killed by fishermen, so they do not carry antibiotics in their system.
These antibiotics don’t just affect the fish, they also promote antibiotic resistance of the bacteria they try to kill off.
In fact, the FDA has said that it has “concerns about the improper use of medically important antibiotics in food products derived from animals, as this practice is one factor that can contribute to antimicrobial resistance in humans.” (source)
A Few Wild Salmons To Try
Sockeye salmon has higher levels of vitamin D and cholesterol than other wild salmon varieties (19). Red Salmon eat only krill and phytoplankton as opposed to fish, so they have the most Astaxanthin, giving them a deep orange hue (20). These fish are very hard to farm, so sockeye is almost always wild, which is reflected in their prized taste (21).
Chinook (king) salmon has nearly twice as many omega-3s as the other fish on this list (19). Chinook salmon can be farmed, so you should always check the source of your fish to make sure it’s wild.
Pacific coho salmon is the most low-calorie and low-fat variety of salmon (19). It contains decent levels of omega-3s and vitamin D, so it’s a great option for people on a restricted diet. Coho salmon can also be farmed, so always check the label (21).