Fish is often recommended as a lean source of healthy protein and omega-3 fatty acids. Great! So long as the fish are raised in a healthy environment, they should be healthy to eat.
The problem is that fish are often NOT raised in a healthy environment, even if they are caught in the wild.
Wild-caught fish that are lower on the food chain
Industrial factories notoriously pollute our oceans and waterways with mercury and other manufacturing toxins. These toxins are taken up by small water organisms and plant life and these smaller organisms are then eaten by larger fish.
This is harmful because the mercury biologically accumulates as it moves higher and higher up the food chain, making large fish dangerous to eat. Since these larger species of wild-caught fish have a high risk of contamination, it’s important to eat smaller fish that are lower on the food chain.
Wild fish are also being over-fished to the point of extinction, which means we have to eat responsibly if we want them to stick around.
When farmed fish are not a more sustainable alternative
Farmed fish were supposed to ease the burden of over-fishing the wild populations, but many fish farms do more harm than good. That’s because industrially farmed fish are often packed into tanks that don’t give them much room to swim.
These cramped conditions are similar to what industrially-farmed livestock endure and, as a result, the fish suffer many of the same health issues.Also similar to industrially-farmed livestock, farmed fish are often fed an unnatural diet of growth hormones, antibiotics, genetically modified corn and other land-based foods that are not found in oceans, lakes or rivers.
Like any animal that is fed an unnatural diet, farmed fish often end up sick. That’s bad for us, because these unhealthy fish make their way to our supermarkets and restaurants, and ultimately onto our plates.
So whether you are environmentally inclined or not, the end result is that responsibly raised fish are also healthier to eat.
Choosing the right fish to eat
Finding fish that are healthier and responsibly raised or caught is a challenge, but there are a few quick tips and smart tools that can help.
When choosing wild-caught fish:
- Stick to fish lower on the food chain (small species fish) to avoid contamination from mercury and other environmental toxins.
- Also choose fish that have been certified by the Marine Stewardship Council (MSC) to ensure the fish were caught responsibly.
When choosing farmed fish, the label should indicate that:
- The fish were raised without antibiotics or hormones.
- They were farmed in low-density (meaning “not cramped“) pens or tanks.
- The fish tanks or pens were not treated with synthetic herbicides.
- The fish were fed a more natural diet that does not include genetically-modified plants or land-based foods.
Specifically which fish to eat & which to avoid
The Monterey Bay Aquarium offers a free Seafood Watch app as a helpful tool you can bring with you to the market or out to eat. The app does not comment on the risk of mercury toxicity, but it does help you to choose responsibly.
Avoid large species fish that tend to be high in mercury
- Orange Roughy
Choose smaller fish that are at lower risk for mercury contamination
Avoid fish that are not responsibly farmed or caught
- Wild & Farmed Barramundi (South Pacific, except Australia)
- Farmed Catfish (Imported)
- Wild Caviar (Mississippi River)
- Wild Chilean sea bass (Chile, unless MSC-certified)
- Wild Cod (unless MSC-certified)
- Wild Crab (Asia, Russia, US Atlantic)
- Wild & Farmed Eel (Worldwide)
- Wild & Farmed Atlantic Flatfish (flounder, sole, halibut)
- Wild Atlantic Salmon (Chile, Scotland, Canadian Pacific, Norway)
- Wild Sardines (Atlantic, Mediterranean)
- Farmed Shrimp (Imported)
- Wild Squid (Asia)
Choose fish that are responsibly raised or caught
- Wild Alaskan king crab (US)
- Wild Alaskan salmon (US & Canada)
- Wild Anchovies (Adriatic Sea)
- Wild Asian carp (Asia)
- Farmed Barrabmundi (US & Australia)
- Farmed & Wild Bass (Hand-line caught in the US Atlantic)
- Farmed Catfish (US)
- Farmed Caviar (American & white sturgeon – US & Canada)
- Farmed Char (Atlantic)
- Wild Chilean sea bass (MSC-certified)
- Wild Crab (Australia, Canada, US Pacific)
- Wild Halibut (Pacific)
- Wild Herring (California, US Atlantic, Lake Superior)
- Wild Longfin Squid (US Atlantic)
- Farmed Mussels (Worldwide)
- Farmed Oysters (Worldwide)
- Wild Oysters (Gulf of Mexico)
- Wild Pacific salmon (Pacific)
- Farmed Rainbow trout
- Wild Sardines (Pacific Canada & US)
- Wild Shrimp (Gulf of Mexico & Oregon)
- Wild Squid (US Atlantic & California)
- Farmed Sturgeon (US, Canadian Pacific)
- Farmed Tilapia (Canada, Ecuador, US)
Good to know
- This fun and informative Ted Talk describes what a healthy, sustainable fish farm should look like.
- Monterey Bay Aquarium has a quick seafood search or use their seafood pocket guides in the U.S.
- The Monterey Bay Aquarium also offers a free (and very handy) Seafood Watch app.
- The Marine Conservation Society has a seasonal guide and Good Fish Guide in the UK.