Best and Worst Fish Choices

Word is spreading that fish is good for your health, but like many matters of health and nutrition, there’s nothing simple about simply eating fish. Even though many varieties can be good for your health, contaminants such as mercury and polychlorinated biphenyl (PCB), found in many types of fish, may be detrimental to your health.

But it gets even more complicated. Beyond choosing fish based on healthfulness (considering things like abundance of healthy omega-3 fatty acids and low concentrations of mercury and contaminants), consuming fish also has an environmental impact. Many environmental advocates have reported that the mismanagement of many large-scale fishing operations has resulted in overfishing (and the plummeting of some wild fish populations). Fish farming, one alternative to wild fish, may help protect these populations, but other groups claim that fish farming has led to other problems, like the overuse of antibiotics to control disease.

Trying to keep track of which types of fish are healthy and safe—not only for you, but also for the environment—can be daunting, to say the least. And here’s why: Making the right choice when it comes to fish means looking for fish that have the highest nutritional content, lowest levels of contaminants and, for those concerned with the environment, the lightest impact on the planet. Let's explore how to make the best choices to meet all of these tricky requirements.

Nutrition and Omega-3s

Nutrients found in foods are usually straightforward.  When choosing fish, people generally want to know which types are highest in omega-3 fatty acids. Concerning omega-3s alone, the following chart ranks the omega-3s in fish from highest content to lowest.

3 oz edible portion
Mackerel, Atlantic 2.6
Chub 2.6
Herring 2.5
King Mackerel 2.2
Chub Mackerel 2.2
Trout, lean lake 2.1
Spiny Dogfish 2.0
Trout, lake 2.0
Salmon, Atlantic, farmed 1.9
Herring, pacific 1.8
Whitefish 1.8
Herring, Atlantic 1.7
Bluefin Tuna 1.6
Chinook Salmon 1.5
Sablefish 1.5
Albacore Tuna 1.5
Whitefish, lake 1.5
Sturgeon, Atlantic 1.5
Canned Sardines 1.4
Pink Salmon 1.0
Smelt 1.0
Striped Bass 0.8
Pollock 0.5
Catfish 0.5
Halibut, Pacific 0.5
Catfish or Cod 0.3
Flounder or Perch 0.2
Snapper or Grouper 0.2
Sole 0.1


When you start to consider contamination from mercury and PCBs (Polychlorinated biphenyl, or industrial chemicals), picking the best fish gets a little more confusing. Organizations such as the Environmental Protection Agency (EPA), Institute of Medicine (IOM), Food and Agriculture Organization of the United Nations (FAO), and the World Health Organization (WHO) have weighed the contamination risk of eating fish against the nutritional benefits it provides. 

To make selection easier, fish is categorized based on average mercury concentration with amounts given in parts per million (ppm). Detailed information and underlying calculations for these lists is available from the EPA.

Best Choices

Species Mercury PPM
Anchovy 0.02
Atlantic Croaker 0.07
Atlantic Mackerel 0.05
Black Sea Bass 0.13
Butterfish 0.06
Catfish 0.02
Clam 0.01
Cod 0.11
Crab 0.06
Crawfish 0.03
Flatfish 0.06
Flounder 0.06
Haddock 0.06
Hake 0.08
Herring 0.08
Lobster (American Spiny) 0.10
Mullet 0.05
Oyster 0.01
Perch, freshwater 0.15
Perch, ocean 0.12
Pollock 0.03
Salmon, canned 0.01
Salmon, fresh/frozen 0.02
Sardine 0.01
Scallop <0.01
Shrimp 0.01
Smelt 0.08
Sole 0.06
Tilapia 0.01
Trout, freshwater 0.07
Tuna, light, canned 0.13
Whitefish 0.09
Whiting 0.05

Good Choices 

Species Mercury PPM
Bluefish 0.37
Buffalofish 0.14
Carp 0.11
Chilean Sea Bass 0.35
Dolphinfish 0.18
Grouper 0.45
Halibut 0.24
Mahi Mahi 0.18
Monkfish 0.16
Rockfish 0.23
Sablefish 0.36
Snapper 0.17
Spanish Mackerel 0.35
Sea Trout 0.23
Striped Bass (ocean) 0.37
Tilefish (Atlantic Ocean) 0.14
Tuna, canned (albacore/white) 0.35
Tuna, fresh/frozen (albacore/white) 0.36
Tuna, yellowfin 0.35
Croaker (White and Pacific) 0.29

Limit or Avoid These Choices 

Species Mercury PPM
King Mackerel 0.73
Marlin 0.49
Orange Roughy 0.57
Shark 0.98
Swordfish 1.00
Tilefish (Gulf of Mexico) 1.45
Tuna, bigeye 0.69

To appropriately use these listings, implement these fish and seafood guidelines:
  • General Adult Population: The US Dietary Guidelines, 2015-2020 recommend consuming two to three servings (eight-12  ounces, before cooking) of fish weekly, using a variety of fish. Selecting fish in the Best Choice and Good Choice lists are encouraged.
  • For women of childbearing age (about 16-49 years old), especially pregnant and breastfeeding women, and women trying to conceive:
    • Each week, eat two to three servings of fish from the Best Choice list OR one serving from the Good Choice list. Eat a variety of different types of fish within the lists.
    • Do not eat fish in the Limit/Avoid List.
    • A serving is four ounces, before cooking.
    • Fish should only be eaten in a cooked state, to an internal temperature of 145 degrees Fahrenheit.
    • If you eat fish caught by family or friends, check the fish advisories.  If there is no advisory, eat only one serving and do not eat other fish for the week.
  • Young Children: Eat two servings of fish weekly from only the Best Choice list using the serving size based on the age of the child.
    • Age 2-5: one ounce per serving
    • Age 6-8: two ounces per serving
    • Age 9-10: three ounces per serving
    • Age 11 and up: four ounces per serving

Environmental Concerns

Finally, there is the concern of depleting the waters of fish and using ecologically damaging methods of fishing and fish farming. Sustainable fishing practices are critical to preventing the extinction of fish species. Advocacy groups, grocery stores and consumers are trying to help reverse trends of overfishing so that the industry as a whole can move toward greater sustainability. Environmental concerns are different from region to region in the United States and throughout the world. Concerns can also change seasonally as well. For the most up-to-date information on selecting fish with the least environmental burden, please check out the sustainability of your fish choices using this listing by the Monterey Bay Aquarium or the Seafood Selector from the Environmental Defense Fund.
Within the field of food, nutrition, and health it is easy for consumers to get mixed messages that result in confusion and frustration. Sensationalism sells and the fear of harm often overshadows the science of health benefits. However, by following the steps above, you can easily develop your own individualized plan for fish consumption that will allow you to reap the health benefits while decreasing your risk of ingesting contaminants.