Salmon. It's ultra-healthy, chock-full of protein, and rich in omega-3 fatty acids that protect your heart, brain, and bones. And Americans seem to know that: It ranks as the third most popular seafood in this country, just behind shrimp and canned tuna. What you might not know, however, is just how filthy this beloved fish can be. A new report from Scotland has found that certain salmon farms have increased their use of pesticides 110 percent over the past four years, polluting the oceans--and your body--with chemicals linked to neurological damage and other ills. Think that's bad? Salmon are also fed a diet increasingly dependent on foods and medications that are suspected of making you fat and upping your diabetes risk, while at the same time making the fish less nutritious. Wild-caught Alaskan salmon doesn't have those, or any of these other problems, and here's why you should be eating more of it.
Gross Factor: Roughly two-thirds of the salmon consumed in the U.S. is imported, with Canada supplying just under 40 percent of that. But Canadian salmon farming is succumbing to "superbugs" of the sea: sea lice, parasites that thrive in ocean-based pens that house thousands, sometimes even millions, of salmon. And the pesticides required to kill this nasty parasite seem to no longer be working, according to a 2011 investigation by Toronto's Globe and Mail newspaper. The reporters found that farmers are now using triple doses of a chemical that's been linked to neurological and developmental problems in humans to kill the persistent parasites.
Better Move: Can't afford pesticide-free wild salmon? Nearly all canned salmon at the grocery store comes from wild Alaskan salmon and is much cheaper than buying from the fresh seafood case. To avoid the toxic chemical BPA used to line canned goods, buy Wild Planet brand, which uses a BPA-free alternative, or look for salmon in foil pouches, which are also BPA free. And always check for sodium, which can get pretty high in canned fish.
Gross Factor: Farmed salmon is one of our largest sources of exposure to chemicals called persistent organic pollutants, or POPs, which include PCBs, DDT, and other industrial chemicals that don't break down when exposed to sunlight, oxygen, or water. Recently, the U.S. government's National Toxicology Program found strong evidence to suggest these chemicals play a role in obesity and diabetes. In fact, a 2011 study published in the journal PLoS ONE found that mice fed farmed salmon containing high levels of POPs gained twice as much weight and developed insulin resistance, a precursor to diabetes, faster than mice fed farmed salmon with some of the POPs removed or mice on a salmon-free diet that included the same number of calories and fat grams.
Better Move: If you want your omega-3s without the POPs, opt for tuna when wild salmon isn't available. Really, it's not all bad! Albacore tuna caught off the California coast is caught while it's young, before its body has had a chance to accumulate high levels of mercury. It's sold by American Tuna, Pacific Fleet, MaryLu Seafoods, Wild Planet, and Wild Pacific Seafood.
Gross Factor: Don't want your fish to burn on the grill? Then, by all means, buy farmed salmon. Not only do the food pellets given to penned fish contain genetically modified corn, but studies have found they also contain a number of industrial chemicals, including PBDE and HBCD, flame retardants added to electronics, cars, and building materials. Research published in the journal Environmental Science and Technology has also revealed perfluorooctane sulfonate, or PFOS, in salmon feed; PFOS was the main component of 3M's Scotchgard fabric protector until it was phased out in 2000 because of disturbing evidence that it caused premature deaths and other organ damage in animals. The chemical doesn't break down in the environment and persists in humans for four years after exposure.
Better Move: Weirdly enough, fish isn't the only hideout for flame retardants in your kitchen. They're also used in citrus-based sodas and sports drinks to keep flavor from separating from the base drink, and they've been found in butter, peanut butter, and sausage, likely as contaminants from food processing and packaging. The solution? Eat fewer processed foods and more fresh, unpackaged food.
Gross Factor: According to a 2012 study conducted by the Norwegian College of Fishery Science, farmed salmon can contain nine times more omega-6 fatty acids--unhealthy fats that have been linked to heart disease and diabetes --than wild salmon does. Ironic, considering that cardiologists often recommend eating fatty omega-3-rich fish like salmon to combat those very diseases. Why the increase? In an effort to reduce pressures on wild fish populations (since salmon are carnivorous, they have to eat large quantities of wild fish to grow), salmon farmers have started supplementing the fish's diets with vegetable oils, which are all high in the unhealthy fats. Not only are they high in unhealthy fats, but they're also likely to be genetically modified (GM), says Pete Bridson, aquaculture research manager at the Monterey Bay Aquarium. According to another new report from the nonprofit Food & Water Watch, GM soy-based feed, a popular alternative in fish farms, lowers omega-3 levels even further.
Better Move: You can always get your omega-3s without any unhealthy omega-6s by using fish oil supplements, which have a lower environmental impact than fish farming, according to the Environmental Defense Fund. Just consult a third-party certifier, such as ConsumerLab.com, to find supplements that aren't contaminated with the same toxic chemicals that contaminate whole fish.
Gross Factor: In addition to supplementing fish food with GM vegetable oils, fish farmers are tossing land-based factory-farm leftovers into these salmon pens, says Bridson. Chicken litter (basically feathers and waste), bonemeal and other poultry by-products are all being added to salmon food, which raises a host of issues. Researchers from the Johns Hopkins University recently discovered that chicken litter imported from China is full of banned antibiotics, Prozac, and caffeine, which are given to chickens to help them survive the stressful and dirty conditions of factory farms. All that could wind up in your "healthy" salmon dinner.
Better Move: Avoid drugged fish and get more protein. Wild Alaskan salmon has three more grams of protein in a three-ounce serving than the farmed stuff.
Gross Factor: The Food and Drug Administration (FDA) has been sitting on an application for genetically modified salmon for a few years now. The fish, bred to contain genes from two separate animals so that they grow faster, contain lower levels of omega-3 fatty acids and certain vitamins than either conventional farmed or wild salmon, and eat far more than conventional farmed salmon, adding to environmental pressure on wild stocks. Independent research also suggests that genetically modifying seafood of any kind could lead to an increase in seafood allergies. If approved--and it's expected to be, anytime now--the FDA wouldn't require genetically modified salmon to be labeled, so you'd have no idea whether you were eating regular farmed salmon or some man-made creation whose effect on your health is a great big question mark.
Better Move: Tell your reps in Congress you don't want lab-created animals hiding behind the fish counter. Sign this petition from the nonprofit Center for Food Safety asking your reps in Congress to ban genetically modified salmon if the FDA approves it.
Stick with wild Alaskan or Pacific salmon, which is healthier and more sustainable. But if you prefer some variety at the seafood counter, check out our other advice on fishmongering:
• 12 Fish You Should Never Eat
• The 10 Healthiest Fish on the Planet
• The 7 Best, and 9 Worst, Places to Buy Fish