Some fish are a good food source, while a few may be unhealthy. It’s important to take enough omega-3 fatty acids, and certain fish can provide them. However, due to factors like mining, sewage, and fossil fuel wastes, heavy metals such as mercury get up in the water and accumulate in our fish. Sadly, low-level mercury poisoning from polluted seafood is a deep concern that can have disastrous health consequences.

Some fish have high levels of mercury. In other words, certain predatory species, such as sharks and tuna, can have high levels of mercury in their bodies. Many of these fish have dietary advisories because, if not eaten in moderation, they may be considered toxic fish. Women should be aware that some fish species are not safe to consume while pregnant or nursing. Children and the elderly are frequently advised not to consume these types of fish.

Having too much mercury in your system can cause brain and nerve damage. It can also have an impact on the development of newborns and young children. Not only that but some fish have been overfished to the point of extinction, which can harm the ocean ecosystem.

Let’s look at the top unhealthy fish you should never eat:

• Farmed Salmon
• Imported shrimp
• King Mackerel
• Shark
• Orange Roughy
• Swordfish
• Marlin
• American eel
• Wild caviar
• Tilapia

Farmed Salmon:

Americans eat a lot of salmon. Unfortunately, the majority is the unhealthy type. Most “Atlantic” salmon are farmed, which means the fish are kept in environments polluted with pesticides, waste, bacteria, and parasites.

Farmed salmon is more likely to produce dangerous toxins such as PCBs, which have been related to insulin resistance, obesity, cancer, and stroke. They are also commonly treated with antibiotics and have higher levels of inflammatory omega-6 fatty acids. Avoid the Atlantic salmon and replace it with wild-caught Alaskan salmon instead.

Imported Shrimp:

Imported shrimp contain pollutants such as E. coli, salmonella, listeria, antibiotics, chemical contaminants, and many others. Instead, try out local shrimp. Look for farmed shrimp that have not been treated with pesticides or antibiotics. You want those from big open ponds that are similar to their natural habitat, or from facilities that filter and recycle water and waste.

Raw shrimp should be firm in texture when purchased. Translucent shells should be greyish green, pinkish brown, or pale pink. Avoid those that have black patches or black edges. Shrimp should be firm and white, with a little scarlet or pink color when cooked. Both should smell mildly salty, not fishy or ammonia-like.

The King Mackerel:

In general, mackerel is an excellent source of omega-3 fatty acids and can be included in a balanced diet. However, king mackerel, particularly those collected in the Pacific Ocean, have high mercury levels. Doctors advise small children and pregnant or breastfeeding women to avoid them.

Shark:

One reason to avoid sharks is that these amazing predators’ populations are declining. Another key explanation is that because sharks are at the top of the food chain, they frequently consume mercury-contaminated seafood. The shark’s mercury levels rise as a result.

Mercury is a neurotoxin that can harm the neurological system and disturb normal brain function, making the meat of the fish toxic. The higher up in the food chain a fish is, the more mercury it is likely to contain.

Orange Roughy:

These slimehead-like fish can live for up to 150 years. That suggests they’ve been exposed to harmful substances like mercury for a longer duration. As a result, they are not the ideal choice for a healthy diet.

Swordfish:

When it comes to avoiding swordfish, the biggest issue is mercury. This huge, predatory fish has high levels of mercury. The mercury content of this fish is so high that women and children should avoid eating absolutely. The guideline for men is to eat no more than one serving each month.

Marlin:

Marlins are distinguished by their pointed fins and long, sharp bills. The population is declining because they are frequently caught or killed by a fisherman while pursuing other species. Because these magnificent fish are at the top of the food chain, they may contain toxins.

Marlin contains high levels of mercury and other pollutants that are potentially dangerous to humans. All striped marlin and most blue marlin should be avoided.  Alternatively, skip the marlin steaks completely. Alternatives include halibut

The American Eel:

Most freshwater eels come from polluted farms, and the population of wild eels is declining. Furthermore, the eels may be tainted with mercury. So you should avoid eating these unhealthy fish. Instead, try American lobster, which is an equally rich meal. If you like the flavor of eel, you can also try squid caught in the Atlantic or Pacific. Sable and haddock can be the alternatives.

Wild Caviar:

Caviar is produced by sturgeon, which takes a long time to grow, making the fishery vulnerable. Smoked salmon with goat cheese and cucumber slices make an excellent appetizer in place of caviar.

Tilapia:

Eating tilapia is as bad as eating bacon. According to a 2008 study, the switch to eating more farmed fish like tilapia is contributing to highly inflammatory diets. It has extremely low levels of beneficial omega-3 fatty acids and,  more importantly, extremely high levels of inflammatory omega-6 fatty acids. Retaining high levels of inflammation in the body can aggravate symptoms of autoimmune disorders and may be related to chronic diseases such as heart disease, cancer, and diabetes.

References:

1. 12 Fish You Should Never Eat. Retrieved from goodhousekeeping.com: https://www.goodhousekeeping.com/health/diet-nutrition/a20705842/fish-you-should-never-eat/
2. 5 Of The Healthiest Fish To Eat—And 5 To Avoid. Retrieved from eatingwell.com: https://www.eatingwell.com/article/69763/5-of-the-healthiest-fish-to-eat-and-5-to-avoid/

3. Nutrition Life. The 5 Healthiest Fish To Eat (And 12 You Should Avoid). Retrieved from nutritiouslife.com: https://nutritiouslife.com/eat-empowered/the-5-healthiest-fish-to-eat-and-12-you-should-avoid/

4. One Medical. 6 Fish To Avoid. Retrieved from .onemedical.com: https://www.onemedical.com/blog/eat-well/healthy-fish-eating-guide/