Are you aware that four fish have been designated by the U.S. Food and Drug Administration ( USDA ) and Environmental Protection Agency ( EPA ) to be unsafe to eat due to their typically high levels of mercury? Making the “do not eat” list are King Mackerel, Shark, Swordfish and Tilefish.
Puffer fish are the most poisonous fish in the world.
Overall, larger and longer-lived fish tend to contain the most mercury ( 4 ). These include shark, swordfish, fresh tuna, marlin, king mackerel, tilefish from the Gulf of Mexico, and northern pike ( 5 ). Larger fish tend to eat many smaller fish, which contain small amounts of mercury.
The Dietary Guidelines for Americans states that to consume those higher amounts, children should only be fed fish from the “Best Choices” list that are even lower in mercury – these fish are anchovies, Atlantic mackerel, catfish, clams, crab, crawfish, flounder, haddock, mullet, oysters, plaice, pollock, salmon, ...
The traditional treatment for mercury poisoning is to stop all exposures. In many cases, chelation therapy is also used. This involves giving a medication (the chelator) which goes into the body and grabs the metal (chelos is the Greek word for claw) then carries the metal out of the body, usually into the urine.
Generally speaking, eating salmon every day is not always recommended, unless you eat small amounts. “The 2020–2025 Dietary Guidelines for Americans recommend that people consume 8 to 10 ounces of seafood per week, especially fish that are lower in mercury, which would include salmon,” says Pike.
Eat at least 2 portions of fish every week, including one of oily fish. Mackerel, sardines, salmon, trout and herring are all examples of oily fish. Remember tuna (whether fresh or canned) does NOT count as oily fish.
Smaller fish—sardines, anchovies, farmed trout, fresh tilapia, arctic char—and bivalves such as scallops, clams, and oysters don't build up as many contaminants as do the large carnivores.
5. Imported shrimp. Why it's bad: Imported shrimp actually holds the designation of being the dirtiest of the "dirty dozen," says Cufone, and it's hard to avoid, as 90% of shrimp sold in the U.S. is imported.
1. Cod. Cod is often considered one of the best white fish and commonly featured in recipes like fish and chips due to its dense, flaky texture. In addition to being relatively low in calories, cod is an excellent source of protein, selenium and vitamin B12.
Fish and shellfish in this category, such as salmon, catfish, tilapia, lobster and scallops, are safe to eat two to three times a week, or 8 to 12 ounces per week, according to the FDA.
While eating fish has nutritional benefits, it also has potential risks. Fish can take in harmful chemicals from the water and the food they eat. Chemicals like mercury and PCBs can build up in their bodies over time. High levels of mercury and PCBs can harm the brain and nervous system.
Fish is a one-stop source of so many vital nutrients that it can maintain a healthy balance in your body, and help fight all sorts of major diseases. Apart from these benefits, eating fish can also improve your metabolism, sleep quality, skin quality, concentration and alleviate inflammation.
While they are both excellent sources of protein and add to your nutrient profile, the benefits of fish tend to be slightly higher than chicken, especially when it comes to the Omega-3 content in it.
Salmon skin is usually considered safe to eat. The skin contains more of the same minerals and nutrients contained in salmon, which may be an excellent addition to any diet. There are some things to consider when choosing whether to eat the salmon skin, such as the source and quality of the fish.
Canned light tuna is in the “Best Choices” category and it is fine to eat 2 to 3 servings per week. We recommend that you eat a variety of fish.
Oily fish – such as salmon, mackerel, anchovies, sardines and herring – contain all-important omega-3 essential fatty acid, which is important for heart and brain health as well as mood regulation.
While they're both highly nutritious, salmon comes out ahead due to its healthy omega-3 fats and vitamin D. Meanwhile, tuna is the winner if you're instead looking for more protein and fewer calories per serving.
The most commonly accepted methods of assessing mercury exposure are to test urine or blood. Both tests usually measure levels of total mercury (elemental, inorganic and organic). Elevated mercury in urine usually indicates exposure to an elemental or inorganic source of mercury, such as from a job that uses mercury.