To help take the mystery out of the meat, we’ve examined the big questions: farmed vs. wild, Atlantic vs. Pacific and sustainability vs. nutritional aspects.
Nutritionally, salmon has a CV that reads like a champion multivitamin commercial. It’s packed with all of the essential amino acids, antioxidants like vitamins A, and E, vitamins D, B6 and B2, calcium, iron, zinc, phosphorus, magnesium, niacin and riboflavin. Then, there are the Omega-3 oils (polyunsaturated, or “good” fats). They've been shown to help lower risk of heart disease by decreasing blood lipids and inflammation in the blood vessels. (That last part may explain why salmon eaters often have glowing skin.) Add the fact that this fish, whether wild or farmed, measures low on the mercury scale, and you’ve got a bonafide superfood.
With stats like these, it’s no wonder that American consumption of the stuff — be it fresh, frozen, canned, farmed or wild — has risen an estimated 35% since 2000. As demand has spiked, so has the practice of farming the fish; farmed Atlantic salmon now accounts for two-thirds of the world’s salmon supply.
Why is farming reserved for Atlantic, not Pacific breeds? Since the Atlantic salmon is endangered in the U.S., it can’t be legally fished in the wild. Farmed fish is generally labeled “Atlantic salmon” in markets, and it often comes from Chile and Canada. While Atlantic salmon is more bountiful and popular in the marketplace, most farmed fish doesn’t win popularity contests with some health proponents, researchers, and organizations like the Environmental Protection Agency and the Monterey Bay Aquarium’s Seafood Watch.
According to these groups, farming often has a negative impact on our oceanic environment, and consumption may add a few health risks too. Some farmed fish are raised in closed, inland tanks, a practice that cuts down on gnarly environmental impact that the practice can have. However, most farmed salmon is raised in coastal waters using open cages, which float waste into the sea. (A farm of 200,000 fish releases waste comparable to the raw sewage produced by a town of up to 65,000 people, according to the Environmental Defense Fund). Chemicals and parasites further pollute waters and mess with wild salmon populations, as does the random salmon who jailbreaks out of the farm to mix with the wild bunch. Further, the amount of chow it takes to raise a fish on a farm — three pounds of wild fish for every one pound of farmed salmon — also gets low marks for sustainability and gives environmental groups pause.
Meanwhile, researchers who have studied the amount of contaminants in wild and farmed salmon also tend to side with the wild. A comprehensive study of 700 wild and farmed salmon fillets found higher levels of PCBs — industrial chemicals that were banned for use in the ‘70s, but are now found in beef, chicken and fish — in farmed salmon. The Environmental Protection Agency has classified PCBs as a probable human carcinogen, while studies link it to reproductive, neurological, and developmental issues. Other banned pesticides and classified probable carcinogens, like dioxins (byproducts of burnt chemicals from waste and industrial treatment), dieldrin, and toxaphene were found in higher concentrations of farmed fish, whereas their wild counterparts contained lower levels of contaminants.
Finally, there are a few treatments which farmed fish undergo and wild do not. Many farmed fish are given antibiotics (to keep them healthy), supplemental omega-3s (as a boost to the consumer) and canthaxanthin (a pigment that gives salmon meat its pink hue). Why the color spike? Since the fish meal that farmed salmon eat are generally void of the fresh krill and shrimp that turns the fish's flesh, well, salmon color, the additive is needed to make the fish look more "wild" to consumers. The FDA deems canthaxanthin safe in small doses, though in one study, high intake of the pigmentation has been associated with the formation of crystal-like deposits in the retina.
As sketchy as some salmon may seem, we still need the stuff. Oddly enough, omega-3 deficiency is ranked as the eighth most preventable cause of death behind major killers like smoking, obesity and high blood pressure. (We tend to consume about 80mg of docosahexaenoic acid [DHA] and 50mg of eicosapentaenoic acid [EPA] per day, the fatty acids found in omega-3s — far short of the recommended 500mg per day.) Studies have also shown that DHA and EPA help normal development of the brain, eyes, nerves, and overall growth and development in humans. DHA supplementation has also been shown to improve memory in young adults and improve pregnancy outcomes. And, since the body doesn’t make these fatty acids for itself, the best way to get these omega-3s and their benefits is through our food.
What’s more, Bruce J. Holub, Ph.D., university professor emeritus at the Department of Human Health and Nutritional Sciences University of Guelph and a 30-year omega-3 researcher, says the benefits of eating salmon outweigh the risks. In a 2009 report to the National Forum on Contaminants in Fish in Portland, Oregon, he indicated that a .001% carcinogenic risk due to contaminants in fish vs. a 30% increased risk of cardiovascular disease due to EHA/EPA deficiency from fish greatly tips the scales in fish’s favor.
If you want to go with the most environmentally sustainable salmon option, check in with Monterey Bay Aquarium’s Seafood Watch Program’s recommendations, which take into account how fishing of a species impacts oceans and ocean life.
But, be sure to consult the group’s findings often, as these recommendations change frequently, according to Alison Barratt, communications manager for the group. “Salmon populations vary each year, and so our recommendations change depending on abundance and projected “returns” of salmon and the quotas set for the catch,” she explains. “Salmon is complicated! It’s caught as it returns to its natal river to spawn, and so there has to be a balance between seeding future salmon stocks and catching some to eat now.”
As of now, a top salmon recommendation from the group is U.S. freshwater coho, favored for its low contaminant level and high omega-3 level. Those looking to make an environmentally sustainable choice without consulting the latest record can generally bet on wild salmon from Alaska.
“We worked with Harvard School of Public Health several years ago to establish some choices that we could classify as ‘super green,’" says Barratt. "These were high in omega 3s, low in contaminants, and a Seafood Watch Best Choice. Only Alaska salmon met all three requirements."
Barratt also suggests eco-minded consumers look for environmentally-friendly fish from the Marine Stewardship Council. “Their blue eco-label can be found on canned, frozen, and fresh salmon from fisheries certified as sustainable to their standard,” she says.
As it turns out, the many-fish-in-the-sea cliché holds true for salmon. Salmon can be a nutritious, wonderful part of the diet — we’ve just got to pick the right one.
Illustrated by Gabriela Alford