Cancer Causing Foods – Part III: Farmed Fish

Most people equate eating fish with healthy eating. That might have been true a few decades ago, but now with the rise of fish farming, the opposite might be the case. Fish farming, also called aquaculture, is the practice of raising fish in a controlled area (sometimes a very small area). It’s shocking that half the fish available for sale isn’t caught in the wild anymore; it’s farmed.

Is fish farming really good for the environment?

Now, you might think that this practice would be good for the environment, because more fish in the wild would be saved. Unfortunately, that’s not true. According to Stanford University professor Rosamond Naylor, “It can take up to five pounds of wild fish to produce one pound of [farm raised] salmon—and we eat a lot of salmon.”

In order to grow salmon or tuna to be large, farmers use huge quantities of various wild caught fish, like sardines, to feed them. In 2006, fish aquaculture used 20 million metric tons of wild fish in their fishmeal. So, no, we’re not saving fish in the wild.

Health concerns

We have heard that fish is rich in Omega-3 fatty acids. That’s because wild non-carnivorous fish eat aquatic plants. On the other hand, non-carnivorous farmed fish are often fed unnatural foods like corn and soy, which don’t contribute these important Omega-3’s. In addition, farmed fish have 20% less protein and tend to be fattier. Not so healthy, after all.

Antibiotics are also a huge concern with farm raised fish. These poor fish are often packed into tiny environments. For instance, twenty-five adult trout might live in a space the size of your bathtub! These horrid conditions lead to a lot of stress and the spread of bacteria, viruses, and parasites. Antibiotics do control outbreaks of infection, but that means you’re ingesting those, too.


Pesticides are another big problem. Fish farmers use toxic chemicals to handle sea lice and other issues. The fact is, a whole host of nasty chemicals have been cropping up in farmed fish:

– Dibutyltin, used in PVC plastics, appear over five times more in farmed mussels than wild-caught.

– Polybrominated diphenyl (PBDE), a flame retardant, is soaring in farmed fish. Ingestion of PBDE has been directly linked to cancer.

– Dioxins, a member of the World Health Organization’s famous “dirty dozen,” appear more than eleven times as much in farm raised salmon than wild. The body stores this poison, which can cause reproductive and developmental problems. Dioxins can also cause cancer.

– PCBs (Polychlorinated biphenyls) were industrial chemicals that were banned in the US in the 1970’s. Sadly, these toxins take a long time to disappear and still can be found in our waters and the sediment. Small organisms ingest them, which is why these chemicals show up so much in the salmon feed.

In addition, a synthetic pigment called Canthaxanthin, is used to give salmon that lovely pink color. Without it, farmed salmon would have a very unappealing gray color. Salmon typically eat krill, which give them the pink hue we have all come to expect. Canthaxanthin has been banned in the UK (but not in America), because it actually can harm the pigment in our eye.

So, if you’re considering what to have for dinner and would like to have a lovely salmon meal, consider seeking out the wild caught version. Skip the PCBs, dioxins and other poisons. I think you’ll find that the meat tastes much better, too!