What is the healthiest fish to eat? What fish should I avoid?

Fish is generally a healthy food high in omega-3 fatty acids, which our bodies do not naturally produce, according to Healthline.

In addition to protein content, the American Heart Association says eating fish twice per week can also lead to better cardiovascular health.

But not all fish are equal. Some are much healthier than others, and there are also considerable environmental concerns related to contaminants like mercury and polychlorinated biphenyls.

Here are the best fish to include in your diet, as well as some to avoid.

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What is the healthiest fish to eat?

These are some of the healthiest fish for your diet, according to Healthline — though read further for more details on how to ensure you’re not contributing negatively to the environment:

  • Alaskan salmon

  • Cod

  • Herring

  • Mahi-mahi

  • Mackerel (other than king mackerel)

  • Perch

  • Rainbow trout

  • Sardines

  • Striped bass

  • Tuna (other than bluefin and bigeye tuna), especially canned light tuna

  • Wild Alaskan pollock

  • Arctic char

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What are the worst fish to eat?

The worst fish to eat are those high in mercury, according to WebMD. Avoid these fish for that reason:

  • Imported swordfish

  • Imported marlin

  • Shark

  • Tilefish

  • King mackerel

  • Orange roughy

Some types of tuna, such as bluefin and bigeye tuna, may also be more likely to have higher levels of mercury, according to WebMD.

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What are the best fish to eat for the environment?

It’s important to think about sustainability, as well as the health implications of consuming fish with contaminants such as mercury or polychlorinated biphenyls. Fish healthy to eat and having minimal environmental impact, according to One Medical:

  • Troll-caught or pole-caught albacore tuna from the U.S. or British Columbia

  • Wild-caught salmon from Alaska

  • Farmed oysters

  • Wild-caught sardines from the Pacific Ocean

  • Farmed rainbow trout

  • Tank-farmed freshwater coho salmon from the U.S.

Just curious? We're here to answer your everyday questions.

This article originally appeared on USA TODAY: What is the healthiest fish to eat? What types of fish should I avoid?