Many people love fish because they’re delicious and are typically healthier than red meat. While fish are a great protein option, there are some species of fish that you should avoid. The following are a few types of fish that you should never eat if you’re conscious about your health.

1) Imported Catfish

Catfish is a staple of Southern cuisine. They’re found in just about any river in the south and can grow to considerable size, making them a great, inexpensive protein. If you buy this at the store, pay close attention to its country of origin.

In Asian countries, many catfish farmers give their catfish hormones to accelerate their growth. This makes them substantially less healthy than free range catfish. Always try to buy free range catfish from America, if possible.

Close-up of medium sized catfish swimming
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2) Tilapia

Tilapia is a really popular choice for many people because it’s a very inexpensive fish. That’s because it’s not particularly good for you. Tilapia will eat just about anything in the ocean, including feces. In fact, their nickname is the “garbage fish.”

This diet makes them high in Omega-6 fatty acids and low in Omega-3s. Since the latter is what you’ll need for heart health, you won’t get the heart benefits from tilapia that you will from other fish.

Tilapia fillets on baking sheet with lemon slices
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3) Eel

This fish is found in many Japanese restaurants. While sushi isn’t that bad for you, eel is not a good choice for those looking to take care of their body.

Eels actually have lots of fat, which causes waste from the ocean to be absorbed into their body. American eels actually have large amounts of farm runoff in them, while European eels are notoriously high in mercury. It’s best just to avoid this fish altogether.

Two eels wrapped around rock underwater
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4) Pangasius

This fish is very popular in Vietnam, where recent immigrants have brought it to the United States. Most pangasius still comes from Vietnam, which is where the trouble arises.

This fish is mainly found in the Mekong River, one of the most polluted rivers in the world. This pollution is absorbed by the pangasius, which has high levels of nitrofurazone and polyphosphates, both of which are carcinogens.

Outdoor fish market, showing variety of fillets
Florencia Viadana on Unsplash

5) Sea bass

This popular fish is known to be very high in mercury. This can cause health problems, especially in pregnant women.

The real problem with sea bass, however, is that it can be mislabeled. In some cases, when a restaurant advertises a sea bass filet, they are actually serving pangasius, which as stated above, is full of cancer-causing pollution. It’s best to just avoid this fish in restaurants unless you’re sure it’s sea bass.

Side view of baked sea bass dish
Patrick Browne on Unsplash

6) Dollarfish

Also known as the oilfish, this fish is not good for people with digestive issues. That’s because it contains a substance that the body simply can’t digest.

The substance is called gempylotoxin, a waxy substance that simply sits in our bellies. While it’s not harmful, for it can cause stomach issues, especially for those prone to digestion problems. If the fish is grilled or fried, that tends to cut down on the gempylotoxin a person ingests.

Hand holding small, silver fish
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