It is often said that eating fish regularly can make people smarter. And China can be said to be a gastronomic system, many cuisines are born from here, and the types are also diverse, in the Chinese culinary cuisine, fish is a big dish, is an indispensable dish on the table.

Nowadays, with the higher and higher living standards, many people will taste different kinds of dishes with different cooking methods, and pay attention to many, but now society is due to various reasons, such as environmental influences or people's desire to smoke, resulting in some fish is not so suitable for eating, if it is not eaten correctly, it may also affect the body.

The nutritional value of fish and its parts

Fish, rich in high-quality protein, easy to digest and absorb, low in fat content, but also contains calcium, phosphorus, potassium, iodine, zinc, selenium and other inorganic salts, as well as vitamin A, vitamin D and B vitamins.

Fish brain, rich in POLYUNSA fatty acid DNA called "brain gold", and phospholipids, contribute to infant brain development and also have a certain effect on the adjuvant treatment of Alzheimer's disease.

Fish maw, known as "marine ginseng" in ancient times, is on a par with bird's nest and shark fin. Fish maw contains biological macromolecule collagen, which is an ideal high-protein and low-fat food by improving tissue nutritional status, promoting growth and development, and delaying skin aging.

Fish scales, which contain choline, enhance memory.

These 6 kinds of fish that are usually visible, or contain formaldehyde and heavy metals, see if you have eaten them

1. Catfish

Catfish, also commonly known as the pond horn fish. Many people like to eat this fish, and its cooking methods are also diverse, many people think that catfish is large and the meat is delicious.

But in fact, it is not so, the living environment of catfish is very bad, even if some of the pollution is more serious or sewers and other such environments can still survive, and catfish often eat some other fish, which will lead to a relatively high content of heavy metals in the body, if you often eat such catfish, the physical damage is relatively large.

2. Deep-sea large-scale edible fish

People know that the general fish that live in the depths of the sea have very high nutritional value, but like some large edible fish, it is best to eat less, and the shark fin we can usually see, this food is a delicacy that cuts off the shark's fins and then cooks them.

You have to know that a shark has only two small fins, once lost, they will lose the direction of flow, and eventually will die, so it is usually best to eat less shark fin, in addition, the large deep-sea fish should eat less, this is because some of the fish with the highest food chain will accumulate more heavy metals, so the damage to the body is also the greatest.

3. Slaughter the fish in advance

In order to seek more profits, some unscrupulous merchants will often take some slaughtered fish to sell, some of which are not fresh or have died.

But in order to make the fish look good, the merchant adds formaldehyde and other substances to the meat, which can make it sell at a good price, and the quality of the fish meat slaughtered in advance cannot be guaranteed, so when buying fish, we must try to choose live fish, so that it is more reassuring to eat.

4. Frozen fish with soft and tender flesh

Fish sold in supermarkets, are stored in the refrigerator, freezer, many marine fish have no way to survive in fresh water, in order to reduce the damage caused by fish death, many merchants will freeze the fish for sale, not only can extend the freshness of the meat, but also can extend the shelf life, convenient storage, convenient transportation.

After freezing will not reduce the taste of fish, but this kind of fish can not be sold in a short period of time, coupled with the lack of perfect freezing equipment during transportation, there will be repeated freezing, such meat may be relatively soft, losing the tender taste of the fish itself.

In the process of thawing, more bacteria will be produced, which will continue to multiply, resulting in the deterioration of fish meat, and often eating such fish will have a great impact on health.

5. Sashimi

I don't know when it began, many people in China began to learn foreign eating methods, directly eat sashimi or eat half-cooked beef, such eating habits are actually not conducive to the health of our people.

In particular, fish meat contains a large number of bacteria, parasites, formaldehyde, if not killed by high temperature, it is likely to enter the human body. Eating sashimi will reduce the gastrointestinal function of the human body, affecting human health, it is best to eat cooked fish, which is conducive to digestion, do not cause damage to the body because of fashion.

6. Large pieces of fish with scales falling off

Under normal circumstances, fresh fish, fish scales are intact, although there is a case of shedding, but it falls off relatively little, not fresh fish or sick fish, often there will be a large number of fish scales falling off.

If you encounter this situation when you buy it again, don't buy it, because it is not fresh, it is likely that there are some diseases or it is about to die, not only affecting the taste, but also some bacteria and viruses.