This week’s chemicals are a bit more controversial than most, as they relate to the debate about farmed and wild salmon.

Demand for farmed salmon has been on the rise since the 1970s, when commercial aquaculture was first established. In fact, global salmon consumption has tripled since 1980, and two-thirds of salmon eaten in the United States is now farmed, according to reports by the World Wildlife Fund. Without the salmon generated through farming, there would only be enough salmon for each person worldwide to have about a serving a year, explained reporter Tamar Haspel in The Washington Post in 2013.

So what’s the big fuss over farmed salmon? Not only is it harder on the environment, it’s also less nutritious, according to In fact, word on the street is that farmed salmon is injected with dye to appear just as blushingly pink as the wild-caught variety.

Of course, the reality of farmed fish colorants isn’t nearly as heart-stopping as the conspiracy theory. Wild salmon derive their pinkish color from snacking on krill, which contains the carotenoids astaxanthin and cantaxanthin. Farmed salmon, meanwhile, receive carotenoid supplements in pellet form, which the FDA requires producers to label as “color added.” Without these added carotenoids, the farmed salmon would be a grayish-white color, says the Coastal Alliance for Aquaculture reform.

Thus, the question is: would you eat salmon if it looked like cooked tuna? Until farmed salmon stop receiving astaxanthin and castaxanthin supplements, I guess we’ll never know.

  • For the record, without these added carotenoids, ALL salmon (wild or farmed )would be grayish-white. They are also important antioxidants for the fish’s diet.

    It’s also highly debatable whether or not farmed salmon is harder on the environment. Farmed salmon require about 1.2 kg of feed to grow 1 kg of body mass. Wild salmon require about 10 kg of feed to grow 1 kg of body mass.

    And both farmed and wild salmon are nearly equally nutritious, there is no serious debate over that fact.