8 Fish and Seafood You Should Avoid

We often hear about the benefits that fish have for our health. And they, in fact, exist and are very relevant. However, what few people know is that the consumption of some types of fish can be quite harmful.

This is because fish and also other seafood can be contaminated, especially by heavy metals (Copper, Lead, Mercury, Arsenic and Cadmium). And the consequence is an excessive consumption of these heavy metals.

Fernanda de Campos Prudente Silva, nutritionist at the Medical Oncology Clinic (Clinonco), highlights that the frequent consumption of food contaminated with toxic metals is harmful because it overloads the liver work and disturbs the balanced functioning of the organism.

How does contamination occur?

Pâmela Miguel, nutritionist at the Functional Nutrition Clinic in São Paulo, points out that mercury is the main heavy metal present in water and the one with the highest degree of toxicity. “The contamination happens as follows: mercury is released into the atmosphere, mainly by burning fossil fuels, and ends up being deposited in the waters. Most fish and seafood are contaminated by it,” she says.

However, emphasizes nutritionist Pamela, the levels of this heavy metal differ greatly, especially among fish. “The type of fish, size, habitat, diet and age are all factors that influence the level of mercury. Predatory fish, that is, those that eat other fish and are at the top of the food chain, are more likely to have a higher level of mercury,” she explains.

Pâmela Miguel adds that the excessive consumption of fish and seafood contaminated with mercury can lead to the accumulation of this metal in the human body and have the following consequences: changes in the central nervous system (delusions, hallucinations, suicidal tendencies), decreased immunity, kidney disorders . “This overconsumption also appears to be associated with some degenerative diseases,” he says.

What should we avoid?

Below, nutritionist Pâmela cites species of fish and seafood that should be avoided or consumed without excess. They are the largest fish and occupy the highest part of the food chain:

1. dogfish
2. Peacock bass
3. Hake
4. Mullet
5. Mackerel
6. Grouper
7. Herring
8. Shrimp (which, due to its filtering characteristic, can absorb most of the impurities in the water)

The nutritionist adds that smaller fish and other seafood are not without mercury, however, in smaller amounts and should be consumed in a balanced way in the diet.

How to choose good fish and seafood for consumption?

The consumption of fish and seafood also brings many benefits to our health, however, some precautions are essential when choosing and buying the product:

Fish

• Check storage conditions: refrigeration or thick layer of ice;
• Body: firm and without injuries. The scales must be preserved. The skin, moist without slimy secretion, shiny and well adhered to the flesh;
• Eyes: Bright, intact and clear;
• Gills: red (don’t buy fish with grayish gills);
• The smell must be characteristic of the sea;
• When buying the fish already cleaned or in slices/fillets: prefer that the cut is done on time and the texture of the meat must be firm.

Cameroon

• Body: curved and with the characteristic color of the species and without spots (each species has a characteristic color);
• Peel and flesh: must be firm.

squid and octopus

• Characteristic smell of the sea;
• Skin: pink and without gelatinous mucus;
• White meat.

lobster and crab

• Vivos: choose the most active;
• Dead: whole shells and claws.

mussels and shellfish

• Choose those that have the shell closed, without cracks or holes;
• The smell must be characteristic of the sea;
• They must be weighed when placed in the hands.

oysters

• When tightened, they must not produce any sound, and when tapping, the noise must be solid and not hollow;
• According to the corrugation of the shell, the age of the oyster is verified: those over three years old are the tastiest;
• Color: grayish;
• Flesh: firm and shiny;
• Characteristic smell of the sea.

What are the benefits of eating fish?

The consumption of fish brings several benefits to our body and our health. Pâmela Miguel cites some of them:

• They are great sources of digestible protein;
• They contain low fat and cholesterol when compared to other meats;
• They are sources of minerals: calcium (important for bone and muscle health), magnesium (important for muscle health), phosphorus (important for brain functions), iron (important to prevent anemia), selenium (important for the immune system) etc.;
• They are a source of important vitamins: vitamin A, D, B complex.

Nutritionist Pâmela adds that, as some fish are more susceptible to contamination, to obtain all the benefits mentioned above without risks, preference should be given to the following species:

• Salmon
• Sardine
• Trout
• Painted
• Cod
• Tuna

In addition to the benefits already mentioned, Pâmela Miguel adds that these fish have a characteristic in common: they are cold water and contain omega 3 – this, in turn, has anti-inflammatory action and is associated with the prevention of several diseases, such as cardiovascular, neurodegenerative disorders, diabetes, in addition to contributing to the reduction of bad cholesterol and increase of good cholesterol.

Fernanda de Campos Prudente Silva adds that fish such as boyfriend, sea bass, among others, are also a good option due to the high concentration of omega 3 – which, in addition to being a potent anti-inflammatory, works by repairing damage to cells and tissues in the body. In addition to helping cognitive function, it improves sleep quality, blood pressure and reduces PMS symptoms.

Nutritionist Fernanda also recalls that sardines, in addition to being rich in omega 3, have good levels of vitamin D, responsible, among many functions, for bone health.

Now you have good guidelines to choose the best types of fish and avoid excessive consumption of those that may pose more risks to your health.

It is also very important to always be attentive when choosing fish and other seafood to ensure the purchase of quality products.

The information contained on this page is for informational purposes only. They do not replace the advice and follow-up of doctors, nutritionists, psychologists, physical education professionals and other specialists.