12 Fish You Should Never Eat—and What to Choose Instead
Learn how to protect your health and ocean ecosystems with smarter seafood choices.
Fish is often marketed as a health food, but not all seafood is created equal. Industrial practices, overfishing, environmental pollution, and high mercury levels have made many popular seafood choices problematic—for your health, for communities, and for the planet. Whether you’re concerned about toxins, unsustainable fishing, or fraud, this guide will help you make better choices. Discover which fish to avoid, the specific reasons why, and the responsible, delicious alternatives worth adding to your diet.
Fish to Avoid Eating—And Safer Alternatives
- Imported Farmed Shrimp
- Imported Catfish
- Sharks, Skates, and Rays
- Atlantic Cod
- Tuna
- Wild Caviar (Beluga and Sturgeon)
- Chilean Sea Bass
- Orange Roughy
- Grouper
- Monkfish
- Tilefish
- King Mackerel
Imported Farmed Shrimp
Why you should skip it: Shrimp is America’s most popular seafood, but about 90% of what is consumed in the U.S. is imported and mostly farmed. The vast majority comes from Southeast Asia, where shrimp ponds are created by tearing down protective coastal mangroves. These farms contribute to significant environmental destruction and are often abandoned when pollution becomes unsustainable, which devastates local ecosystems. Farms are notorious for antibiotic use and poor regulation. Consuming imported farmed shrimp may expose you to chemical contaminants and harm global biodiversity.
Eat this instead: Look for U.S. wild-caught shrimp, Key West Pinks, Rock Shrimp, or Gulf Shrimp. Wisconsin Royal Reds are also a good choice but beware of mislabeling and ensure you’re not getting high bycatch varieties like some Argentinian Royal Reds.
Imported Catfish
Why you should skip it: A large proportion of imported catfish—especially from Vietnam, such as pangasius (often labeled as basa or swai)—is farmed under conditions with questionable oversight and lax regulation. These operations can involve heavy antibiotic and chemical use due to crowded conditions. There’s a history of food fraud, with other fish being substituted and sold as catfish, potentially exposing consumers to unknown contaminants. Imported fish can travel long distances, increasing the risk of spoilage or improper handling.
Eat this instead: Seek out U.S.-farmed catfish only. Regulations in the U.S. are much stricter, with more oversight regarding antibiotics, contaminant levels, and environmental impact.
Sharks, Skates, and Rays
Why you should skip them: These apex predators accumulate the highest concentrations of mercury and other toxins over time through a process called biomagnification. Shark fishing has led to rapid population declines, threatening extinction for many species. Additionally, rays and skates are overexploited, and shark finning—a practice of removing fins and discarding the rest at sea—contributes to inhumane treatment and ecosystem collapse.
Expectant mothers, children, and anyone concerned about mercury exposure should avoid these species completely.
Eat this instead: Choose U.S. wild-caught salmon or other smaller, short-lived fish like tilapia (U.S.-farmed), which are far less likely to accumulate dangerous toxin levels.
Atlantic Cod
Why you should skip it: Atlantic cod was once a staple of the North Atlantic economy, but decades of overfishing have brought stocks to the brink of collapse. Despite some management improvements, populations have not recovered and the food chain has been permanently altered. Cod fisheries are still vulnerable, and bycatch from cod fishing leads to further problems among other struggling species.
Eat this instead: Pacific cod is a viable substitute, as populations are healthier and fisheries are better managed.
Tuna (Bluefin, Yellowfin & Bigeye)
Why you should skip it: Tuna is the U.S.’s second most popular seafood after shrimp. However, the rapid rise in demand is depleting tuna populations—particularly Atlantic and Pacific Bluefin, Yellowfin, and Bigeye. These large fish are slow to mature, reproduce infrequently, and are vulnerable to overfishing. Additionally, they have high mercury concentrations, increasing the risk of neurotoxicity, especially in children and pregnant women. Most tuna is caught using unsustainable methods—like longlining or purse seining—that threaten sea turtles, sharks, and seabirds due to high bycatch rates.
Eat this instead: For sandwiches or salads, try tinned sardines or organic tinned chicken for a similar protein boost. If you love canned tuna, choose Skipjack, which is less likely to be overfished, smaller (and therefore less contaminated), and matures more quickly. Additionally, look for tuna that’s pole- or troll-caught—methods with much lower bycatch rates.
Wild Caviar (Beluga and Sturgeon)
Why you should skip it: The beluga sturgeon and related species are critically endangered due to demand for their eggs. Overfishing, pollution, and habitat loss (particularly from dam building) threaten these slow-growing fish even further. Caviar production removes mature, reproducing females from shrinking populations, making it even harder for wild stocks to recover. Some types of caviar are even harvested from fish at risk of extinction.
Eat this instead: For a sustainable treat, opt for American lake sturgeon or hackleback/shovelnose sturgeon caviar from the Mississippi River system. Some California caviar brands use only sustainably farmed eggs.
Chilean Sea Bass (Patagonian Toothfish)
Why you should skip it: Once heavily marketed as “Chilean sea bass,” this deep-water fish is severely overfished, with illegal and unregulated fishing leading to near-commercial extinction in some regions. The species is also long-lived and slow to recover. Greenpeace and other organizations warn that stocks are so depleted that continued demand could cause commercial extinction within years. Chilean sea bass is also high in mercury.
Eat this instead: Get a similar flavor and texture with U.S. hook-and-line caught haddock, a far more sustainable choice.
Orange Roughy
Why you should skip it: The orange roughy is extremely long-lived, taking 20–30 years to mature. Excessive fishing throughout the 1980s and 1990s caused populations to plummet and many stocks have never recovered. Orange roughy also contains elevated mercury levels due to its age and size. Vulnerable populations, slow growth, and bioaccumulation of toxins make this a species best avoided.
Eat this instead: Try sustainably caught Pacific red snapper or U.S. farmed tilapia (if properly sourced) for a white fish with mild flavor.
Grouper
Why you should skip it: Grouper species are susceptible to overfishing and often have moderately high mercury levels. The fish are slow-growing and late to mature, and their populations have not yet rebounded from decades of exploitation. Grouper is also commonly subject to seafood fraud: DNA testing reveals that, in many restaurants, what’s labeled as grouper is often pangasius, king mackerel, or weakfish—a practice that obscures true sourcing and may expose diners to unforeseen allergens or contaminants.
Eat this instead: Choose Pacific Ocean-caught striped bass or U.S. farmed hybrid striped bass for similar taste and texture without the environmental cost.
Monkfish
Why you should skip it: Monkfish, sometimes called “the poor man’s lobster,” is often caught via bottom trawling, a destructive practice that razes seafloor habitats and leads to high bycatch of threatened species. Monkfish populations are also vulnerable, and when demand rises, illegal and unregulated fishing increases. Depending on the region, monkfish may carry high mercury levels.
Eat this instead: Select sustainably sourced lobster or U.S.-caught pollock for a more responsible option.
Tilefish (from the Gulf of Mexico)
Why you should skip it: Tilefish from the U.S. Gulf of Mexico contain some of the highest mercury concentrations recorded in any commercial fish species. Consumption or even occasional meals can lead to mercury poisoning, especially for sensitive groups. Consumption advice varies by region, but it is safest to avoid altogether if you cannot trace the specific source. Note: Tilefish from the Atlantic is considered less risky but still should be eaten sparingly.
Eat this instead: Switch to Atlantic or Pacific flounder or farmed rainbow trout.
King Mackerel
Why you should skip it: King mackerel is high in omega-3s but also ranks among the highest in mercury content. The U.S. Food and Drug Administration recommends that women and children avoid king mackerel entirely, and everyone else limit their consumption to once a month or less. Spanish mackerel is also worth avoiding due to similarly high mercury levels. In contrast, Atlantic mackerel is safer and more sustainable, with much lower levels of mercury.
Eat this instead: Opt for Atlantic mackerel, a small, fast-growing fish with high nutritional value and minimal contaminants.
Table: Summary of Fish to Avoid vs. Safer Alternatives
| Fish to Avoid | Reason | Better Alternative |
|---|---|---|
| Imported Farmed Shrimp | Environmental ruin, pollution, antibiotics | U.S. wild-caught or Gulf Shrimp |
| Imported Catfish | Poor regulation, fraud, contamination | U.S. farmed catfish |
| Shark, Skate, Ray | High mercury, extinction risk | U.S. wild-caught salmon |
| Atlantic Cod | Overfishing, population collapse | Pacific cod |
| Tuna (Bluefin, Bigeye, Yellowfin) | Overfishing, mercury, bycatch | Skipjack tuna, sardines |
| Wild Caviar | Endangered sturgeon | Farmed U.S. caviar |
| Chilean Sea Bass | Severe overfishing, mercury | U.S. caught haddock |
| Orange Roughy | Overfishing, slow recovery, mercury | Red snapper |
| Grouper | Overfishing, fraud, mercury | Striped bass |
| Monkfish | Habitat destruction, high bycatch | Lobster, pollock |
| Tilefish | Very high mercury | Flounder, trout |
| King/Spanish Mackerel | High mercury | Atlantic mackerel |
Why Are Some Fish So Risky?
Problems with commercial fishing and aquaculture include:
- Overfishing and Collapsed Stocks: Many targeted species—especially long-lived, late-maturing fish—reproduce slowly and are unable to recover from unchecked harvesting, leaving populations at historic lows.
- Mercury and PCB Contamination: Larger predatory fish accumulate dangerous amounts of mercury and other heavy metals, posing health risks.
- Sustainability and Environmental Damage: Poor aquaculture and destructive fishing practices destroy habitats, pollute water, and put additional pressure on threatened species.
- Seafood Fraud: Mislabeling and food fraud mean consumers aren’t always getting what they pay for, which can expose them to unexpected species or allergens.
How to Make Smarter Seafood Choices
To enjoy the benefits of seafood—while avoiding health and environmental risks—consider these key practices:
- Check sources and favor U.S.-caught or farmed fish, as U.S. regulations are generally stricter regarding sustainability and contaminants.
- Look for certification labels like Marine Stewardship Council (MSC) for wild fish and Aquaculture Stewardship Council (ASC) for farmed seafood.
- Choose smaller fish like sardines, anchovies, and Atlantic mackerel which reproduce rapidly and are low in mercury.
- For canned fish, look for Skipjack tuna (the smaller species) and brands that are pole- or troll-caught.
- Avoid high-risk fish if you are pregnant, breastfeeding, or serving young children.
Frequently Asked Questions (FAQs)
Q: Are all types of shrimp unsafe?
No, but nearly all imported farmed shrimp is best avoided due to poor environmental and health standards. U.S. wild-caught and some U.S.-farmed options are far better.
Q: Is it ever safe to eat tuna?
Consuming small amounts of Skipjack tuna (light tuna in cans) is relatively safe for most adults—but limit your intake due to mercury concerns. Always check sourcing for sustainability and bycatch concerns.
Q: How can I avoid seafood fraud?
Buy from reputable fishmongers, request precise labeling, and prefer whole fish (which is harder to mislabel). U.S. labeling requirements have recently improved, but risks remain with imported products.
Q: What are the healthiest fish overall?
Sardines, anchovies, wild Alaska salmon, U.S. farmed rainbow trout, and Atlantic mackerel are consistently high in nutrients, low in toxins, and usually sustainably managed.
Q: What about tilapia?
Tilapia can be controversial—avoid Chinese farmed tilapia due to environmental and antibiotic concerns. U.S.-farmed tilapia is generally safe and sustainable when eaten in moderation.
Expert Tips for Sustainable Seafood
- Consult the Seafood Watch guide by the Monterey Bay Aquarium for current recommendations.
- Use apps or wallet cards to check sustainability ratings while shopping.
- Rotate seafood types to reduce overreliance on any one species and support biodiversity.
- When in doubt, prioritize wild-caught over farmed—but always check for responsible sourcing.
Final Thoughts
Seafood can be an excellent source of protein and healthy fats, but only if you make informed choices. Avoid the 12 risky fish highlighted here, opt for responsibly sourced alternatives, and always stay up to date with the latest expert advice to protect your health—and the ocean’s future.
References
Similar Articles
Read full bio of medha deb
