Meat has the lowest fat content.
The average fat content of pork is 30%, chicken is about 9%- 14%, and aquatic products are about 1%- 10%.
For example, shrimp: 100g shrimp, which contains 18. 3g protein, 1. 6g carbohydrates and only 0. 5g of fat is basically negligible. Shrimp with the same weight, like white rice, has only 70% calories and is easier to get full. Therefore, eating shrimp is more troublesome than shelling, and there is really no disadvantage. It is a high-quality protein with low fat.
Rich in unsaturated fatty acids
White meat and red meat have different fat types. Most of the fat in red meat is saturated fatty acid. Most of the fats in aquatic products such as fish and shrimp are healthy unsaturated fatty acids.
100 grams of salmon has a calorie of 139 kcal and a protein content of 17. 2g, the carbohydrate content is 0 and the fat content is 7. 8g。 Although the fat content is close to that of pork tenderloin, it is rich in unsaturated fatty acids. And it is a special ω-3 fatty acid among unsaturated fatty acids. It has two important substances, DHA and EPA. It is not only beneficial to the development of children's brain and nervous system, but also can prevent cardiovascular diseases and increase the health of the heart for the elderly. Omega-3 fatty acids are very important and must be obtained from food.
In addition to salmon, deep-sea fish such as cod, yellow croaker and saury are rich in Omega-3 fatty acids.
Shellfish food is low in calories and high in calcium.
Shellfish such as clams, clams and scallops are not only cheap, but also low in calories. Every 100g of edible seafood meat has only over 40 calories, which is almost the same as that of fruit with the same weight, even less than half of that of white rice. Moreover, these shellfish are also rich in calcium.
China Nutrition Society cooperated with relevant medical colleges and universities to do a lot of rigorous experiments on "food compatibility". However, the results of various studies show that no group of legendary foods will cause abnormalities in our bodies.
In a word, it is generally pseudoscience to talk about toxicity without dose. Instead of carefully matching food, it is better to change the diet structure of high carbon, water and fat through a variety of natural ingredients.
Shrimp, for example, contains arsenic. When arsenic combines with vitamin C, it produces a substance called arsenic trioxide, which is the main component of arsenic.
But it may actually lead to poisoning, which requires the following three conditions:
First of all, most of the arsenic contained in shrimp is stable organic arsenic, and only a very small amount of inorganic arsenic will react with vitamin C, so according to the calculation, it takes 150 kg to eat shrimp once. In addition, you should also take a large dose of vitamin C, such as dozens of pounds of fruit. After these two substances enter our bodies, we need a specific environment for chemical reactions. For example, the length of stay in the intestine at the same time, the appropriate temperature, enzymes and other conditions. And these are not in line with the actual situation in our daily life, and the possibility of realization is almost impossible.
There are persimmons and crabs, because persimmons contain tannic acid, which can combine with the high protein in crabs to form a water-insoluble precipitate: tannic acid protein. When there is a large amount of gastric acid in the stomach, tannic acid protein and pectin and fiber in food stick food residues together, forming stomach persimmon stone in the stomach, causing stomach discomfort.
But the premise is that the persimmons here must be immature raw persimmons, because the tannic acid in raw persimmons can reach more than 4%, and most people will not eat many raw persimmons that are not delicious. However, the tannic acid content of mature sweet persimmon will be as low as 0. 1%, and such a low content will not have any impact on the human body.
1. The food is not clean and the heating is not complete.
Seafood grows in water, so it is easy to get infected with parasites. In addition, seafood itself has high protein content and high water content, which is slightly stale and easy to breed a large number of bacteria. For example, seafood contaminated by Vibrio cholerae can be killed by heating at 55 C10 minutes or boiling, but if it is not thoroughly cleaned and cooked, it will lead to diarrhea.
2. Inappropriate diet
For example, taro and yam containing plant alkaloids, if not cooked, will cause nausea, vomiting and diarrhea. In addition to taro yam, many plants such as beans also contain plant alkaloids. If it's eaten with seafood, it's probably not a seafood problem.
3. Lactose intolerance
People who are lactose intolerant can't fully digest lactose in dairy products because of the lack of lactase in their bodies, so they will have allergic symptoms such as diarrhea, abdominal distension and abdominal pain.
4. Food allergy
For Asians, eggs, dairy products, bean products and seafood are the most allergic foods. Theoretically, any food containing protein may cause allergies. Because after protein enters our body, it is easy to be attacked by the immune system as an invading pathogen.
Common shellfish seafood, including scallops, clams, clams, scallops, oysters and so on. It is a fat-reducing food with high protein and low fat, rich in minerals such as calcium. For example, the zinc content of three kinds of oysters meets our daily needs. As we said before, zinc is very important for children's brain and body development, and it can improve immunity. A bowl of mussels can meet the iodine demand for one day, which is beneficial to the health of thyroid.
Compared with other seafood, shellfish will make us feel more delicious, because shellfish need amino acids to fight the salt in seawater, so it accumulates rich flavor glutamic acid. Therefore, the higher the salinity of seawater, the more delicious shellfish will be.
Selection and preservation of shellfish
Shellfish is rich in protein, but because of its strong enzyme activity, it decomposes very quickly, and the meat is easy to deteriorate. When shopping, be sure to choose fresh shellfish with intact shells. Touch the shells with your hands and they can be closed immediately. The best way to preserve shellfish is to put them on ice and cover them with a wet cloth. Never soak them in melted ice water, because there is no salt in ice water, which will make them die and become stale.
How do clams spit sand?
The heat of clams (also called flower shells) and clams is also the lowest among shellfish, lower than that of apples. However, because Meretrix meretrix is a kind of shellfish that likes to drill sand, if the sand is not clean, it will affect the taste. A relatively simple method is to put the Meretrix meretrix into clear water, sprinkle some salt, soak it in salt water and let it stand for about two hours. If you are in a hurry to eat, you can change the cold water into warm water of about 30~40 degrees. Clams are more active in warm water and spit out more sand than in cold water.
How do oysters open their shells?
Oyster (also called oyster) is the softest seafood in the ocean, and you can understand it as filet mignon in steak. Because the muscles that make shellfish and seafood tight are hard, the adductor muscles of oysters only account for110 of their body weight, and other thin and brittle tissues account for more than half. Therefore, westerners like to dig oyster meat out of its shell and eat it raw immediately, because this way can best understand this particularly tender taste. So if you want to eat oysters in the west, opening oysters is also a special technology. You need to use an oyster knife. The surface of the oyster is very sharp, and you will cut your hand if you are not careful.
However, people in China are still used to eating cooked food, so oysters with great technical difficulty can be cooked easily by steaming and microwave. Steam the oysters in a steamer for 2-3 minutes, or bake them in a microwave oven for half a minute, and the oysters will open. However, the opened oyster is not ripe, so you can take it out and remove half of the shell, then add onion, ginger, garlic and seasoning to continue steaming until it is cooked.
Compared with river shrimp, sea shrimp contains more unsaturated fatty acids, such as DHA and EPA in Omega-3. However, shrimp meat is big, tastes more firewood and smells heavier than river shrimp.
The shell and meat of shrimp contain calcium, phosphorus and astaxanthin, which are the main components of bones and teeth. Astaxanthin is a stronger antioxidant than vitamin C, and it is the "king of antioxidants", which can help us delay aging.
Must the shrimp line be removed?
Shrimp line affects the taste, but it is very troublesome to go to shrimp line, so many people will hesitate to go. Shrimp line belongs to the digestive tract of shrimp, and the black thing inside is the waste that has not been excreted in the intestine. Therefore, from a health point of view, it is recommended to remove it before eating. But if you accidentally eat it, don't worry too much, because the bacteria in the shrimp line will be killed after high temperature treatment.
Some students in the south like to eat drunken shrimp. Although it tastes good, wine can't kill bacteria or parasites. Therefore, from the perspective of safety, I suggest that you try not to eat.
Is the shrimp head rich in nutrition or heavy metals exceeding the standard?
Sometimes, we will find that the color of shrimp head is black, and many people may ask, is this heavy metal?
In fact, this color is due to some melanin produced by feed or enzyme conversion, which has nothing to do with heavy metals. Whether the heavy metal content is high or not depends on water and feed, not on whether the shrimp head is black or not. The water quality and feed of shrimp cultured regularly are guaranteed to a certain extent, so there is no need to worry about excessive heavy metals.
But the head of shrimp contains all the organs of shrimp, including stomach and ovary (which is what we usually call shrimp yellow). Viscera is easier to enrich heavy metals than muscle tissue, so the content of heavy metals in shrimp head is indeed higher than that in shrimp meat. It is recommended not to eat viscera. However, the shrimp yellow inside the shrimp head is the same as crab yellow, with a slightly higher cholesterol content, but there is still a lot of vitamin A, which normal people can safely eat.
Can eating shrimp skin supplement calcium?
If you only look at the data, eating shrimp skin can really supplement calcium. Its calcium content is 99 1mg/ 100g, which is more than 7 times that of milk. But in fact, eating shrimp skin to supplement calcium is not a good choice, because shrimp skin is very light, and you can't eat much at a time, so you can't get much calcium. Compared with milk, shrimp skin is not easy to chew, and the calcium in it is not easy to be absorbed by our bodies. The most important thing is that 100g shrimp skin contains 5057 mg of sodium, and nitrosamines, a strong carcinogen of salted meat, which we mentioned before, so although the amount is small every time, it is still not good for the health.
Although aquatic products are good things rich in high-quality protein and low in fat, people's awareness of aquatic products' food safety is getting stronger and stronger as the industrial pollution of oceans and rivers is paid more and more attention.
biomagnification
First of all, a concept of popular science is called biomagnification. Simply put, some pollutants in the environment, such as heavy metals and pesticides, are difficult for our bodies to decompose, and will accumulate from bottom to top along the food chain, and the concentration will increase.
In aquatic products, phytoplankton-herbivorous fish-carnivorous fish also constitute the food chain. Mercury (also known as mercury) is a typical compound that can be biomagnified. Therefore, from phytoplankton, herbivorous fish to small carnivorous fish, the mercury concentration is 23, 34, 53 and 485 times of the original mercury concentration in water, and mercury is transported along the food chain. Mercury mainly damages human central nervous system, digestive system and kidney.
Refuse to eat shark fin
Due to the biomagnification of large carnivorous fish, more harmful substances such as mercury are gathered in the body, and mercury can enter the fetus through the mother, which affects the development of fetal nervous system. Therefore, the US Food and Drug Administration and the US Environmental Protection Agency jointly issued a notice, clearly pointing out that women and children should avoid eating seven kinds of fish with high mercury content, such as shark, swordfish, longevity fish, square head fish, mackerel, marlin and bigeye tuna.
Therefore, the shark fin praised by Chinese people should not be eaten in the future, because it is made of shark fin. Shark is a large carnivorous fish and one of the longest-lived fish in the ocean, which means that biomagnification has accumulated more pollutants in its body for a long time. The mercury content accumulated in sharks may be 10,000 times that in water.
Shark's fin is called shark's fin because it has ribs in the shape of vermicelli, which contains about 80% collagen. Due to the lack of tryptophan, collagen is not a high-quality protein. And cooking can't remove the toxicity of mercury or other heavy metals. Students watching the documentary may also know that sharks usually cut off their fins and throw them back into the sea to die, which is very cruel. Therefore, whether for environmental protection or for our own health, we should refuse to eat shark fin.
What kind of fish can I eat?
Eating deep-sea fish is the best way to obtain DHA. Which fish are relatively safer? Like salmon, arowana, perch, yellow croaker, saury, sardine and pomfret, we can usually eat more fish with low mercury content and high DHA content.
Generally speaking, the order of mercury concentration is: marine fish > lake fish > river fish, so the DHA of freshwater fish is not high, but there is no need to worry about mercury pollution. As long as it is bought in a regular supermarket or food market, it will go through the most basic inspection before entering the market. It is no problem to buy it.
Due to the uncertainty of environmental pollution, try not to eat wild fish, because the source and quality of fish can not be guaranteed, which may hide greater security risks. In addition to heavy metals and parasites, some toxins may accumulate. For example, some fish will accumulate toxins in their bodies by preying on toxic algae, small fish and shrimp. Ciguatoxin and tetrodotoxin are common, and people are easy to be poisoned if they eat them.
The red meat unit says that salted meat products can't be eaten because they will produce strong carcinogens, and so will fish.
Salted fish is a very popular dish in China, but the International Agency for Research on Cancer has listed China salted fish as 1 carcinogen, and the World Health Organization has clearly pointed out that China salted fish can cause cancer, and frequent consumption of salted fish will increase the risk of nasopharyngeal carcinoma.
Are there parasites in sashimi?
Many people will order a sashimi platter when they go to Japanese food stores, which will contain all kinds of sashimi, sweet shrimp, arctic shellfish and so on.
The parasites that may be carried in sashimi are mainly anisakis. Only sufficient heating can kill it. Moreover, proper heating treatment will stretch the structure of protein, which is more conducive to the catalytic decomposition of protease in our body and promote the digestion and absorption of protein.
So how can we avoid parasites to the greatest extent?
Choose a regular restaurant
The parasite problem can only be controlled at the source. The United States and European countries have promulgated targeted food safety regulations, stipulating that fish must be pretreated. The most effective way to kill anisakis is high temperature, but in order to keep the taste of fish, the rapid freezing method is mainly used at present. The US Food and Drug Administration stipulates that fish must be frozen at MINUS 20 degrees for 7 days (if it is MINUS 35 degrees, it can be shortened to 15 hours) before it can be put on the market, while the EU standard is freezing at MINUS 20 degrees for more than 24 hours.
Because imported marine fish need to be tested by the entry-exit inspection and quarantine department, you don't have to worry too much about parasites when choosing a regular restaurant.
Choose to eat farmed deep-sea fish instead of freshwater fish.
Most natural wild marine fish carry parasites, but deep-sea cultured marine fish in Norway, Scotland, Chile and other places have strict control over feed and deep-sea environment, and will also vaccinate fry and disinfect fishermen. With the development of modern aquaculture technology, the risk of parasites can be effectively controlled. For example, the salmon we usually talk about is generally the salmon cultured in deep sea in Norway.
If you have traveled to Yunnan, you may have eaten a local freshwater salmon. There are also some places in China, such as Huairou in Beijing and Hunan, where "fresh water salmon" is cultivated. Its appearance and meat quality are very similar to salmon, which is still difficult to distinguish with the naked eye, but it is not a real salmon, but a kind of fish called rainbow trout. Because lake fish and river fish have more parasites than sea fish, they are easy to be infected with other parasites such as clonorchiasis and paragonimiasis, and the risk is greater without inspection and quarantine, so freshwater fish must be cooked before eating.
Some "raw food" is actually cooked
Perhaps contrary to what everyone thinks, the arctic shell is not raw, but cooked. Arctic shellfish are mainly distributed in the cold water areas of the Arctic Ocean, the North Pacific Ocean and the North Atlantic Ocean, which can be regarded as a veritable "Arctic" shellfish. Canada is the most important producer, and 90% of the arctic shellfish in the world come from Canada. After they are caught, they are usually cooked, frozen and packaged immediately to ensure the freshness of food, so there is generally no chance of being infected with parasites. This is probably why it is difficult for many people to accept sashimi, but they can accept arctic shellfish.
In addition, we usually buy it in supermarkets, and the imported Arctic sweet shrimp produced in Canada is also cooked and frozen, and can also be eaten directly after thawing.
Don't buy raw food online.
Because it is generally difficult for online stores to monitor whether their transportation and storage processes are safe and hygienic, it is recommended that you try not to buy these fresh foods online. If you want to buy, you must buy seafood specially used for raw food quarantine on the product details page with the inspection and quarantine certificate of inbound goods.
Generally speaking, eating raw food is not healthier than eating cooked food. In addition, from the perspective of reducing fat and increasing muscle, proper cooking can also improve our absorption rate of protein. Of course, for many Japanese food lovers, Japanese food is more about food, and it is equally important to have fun. Within the risk control range, it doesn't hurt to eat occasionally.
The scientific name of crayfish is Procambarus clarkii, which is a kind of freshwater crayfish and is related to crayfish in the sea. When you hear the scientific name, you will realize that it is not a native shrimp in China. Do you have crayfish in China? There are also, but the local crayfish are on the verge of extinction because of its strong adaptability to the environment and rapid reproduction. So what we can see in the market now, the well-known crayfish, is Procambarus clarkii
1927, the Japanese introduced a small amount of Procambarus clarkii from Hawaii, USA, not for eating at first, but as feed for bullfrogs. About two years later, crayfish flowed into Nanjing from Japan and finally thrived in China because of its strong adaptability. This is also the source of rumors that crayfish were introduced to China by the Japanese to destroy their bodies during World War II. Many people think crayfish is dirty, so westerners don't eat it. In fact, crayfish has been eaten in the United States for more than 100 years, and it is also a very common ingredient in the United States, but no one will eat it in China. For example, we will cook spicy crayfish, braised pork, garlic, thirteen incense and so on. In the United States, it is usually cooked with potatoes and corn, then mixed with a seasoning called Cajiang powder, and sometimes made into lobster cakes.
Is crayfish safe?
Now all the crayfish we buy are farmed on a large scale. In order to prove their standardization, many merchants will advertise that their lobsters are white-cheeked, so they are no longer the wild crayfish in the stinking ditch. Moreover, crayfish also prefer clean water and fresh food. It can survive in the ditch only because of its tenacious vitality, not its preference.
China is a big exporter of crayfish, and its cooked food products include shrimp tails, shrimp, shrimp paste, whole shrimp and so on. 90% of crayfish in the European market come from China, which can pass foreign food inspection, so it is naturally impossible for heavy metals to exceed the standard. With the quantity and quality of crayfish we eat in a year, it is far from harmful.
How to eat crayfish healthily
Heavy metals are mainly concentrated in the head. Don't eat shrimp heads and shrimp lines, don't suck your cheeks. You can safely eat shrimp tails and pincers.
Well, since it is a freshwater crayfish, like freshwater fish, it will have the risk of parasites, so it must be cooked. Don't eat half-baked crayfish. If you buy crayfish and cook them yourself, it is best to put them in clear water for a period of time to let them spit out the sediments in their bodies.
How to eat from the perspective of increasing muscle and reducing fat? The protein content of crayfish is very high, accounting for about 16%-20% of the total weight. The fat content is very low, and the meat is easy to digest. In addition, shrimp meat is rich in magnesium, zinc, iodine, selenium and other important trace elements, and it is a high-quality protein.
Everyone eats a catty of shrimp, and a meal of protein is enough. Try not to choose the type of frying, such as spicy crayfish, spicy crayfish, such as thirteen spices, braised pork and garlic, which are all better choices.
Of course, the most important thing is that if you can have dinner, don't eat it as a midnight snack. If it can be paired with vegetables and staple foods, it is a very healthy meal.
There are three ways to consume calories, one is basal metabolism, which accounts for 60%-75% of our daily consumption, and the other is physical activity and food thermal effect. It can be understood that one is active exercise, and the other is because after we eat food, our bodies do passive exercise to digest and absorb the nutrients in the food.
According to the food we eat, the energy we consume is different. Protein is the highest, reaching 30-40%, far exceeding fat (4-5%) and carbohydrate (5-6%). That is to say, when you eat carbohydrates and fats, 95% of them are converted into sugar and fat in your body, but when you eat protein, you have consumed 1/3 calories in the process, which is the same. This is also the reason why people eat meat in winter or cold places to keep out the cold.
Secondly, the difficulty of transforming the food we eat into fat is very different. Carbohydrates and fats are easier to absorb and store. If we eat too much carbohydrates, we will turn into fat in large quantities.
Finally, our body's absorption rate of protein is adjusted according to the body's needs, and the excess protein will not be stored as fat. Therefore, the meat we eat, whether it is red meat or white meat, as long as the fat content is low enough, we don't have to be afraid to eat meat because we are worried that it will get fat.
Some people may say that they have heard a theory that protein will hurt his kidney if he eats too much.
The reason for this is that when protein's intake exceeds 1.9g per kilogram of body weight, the nitrogen content in the body will increase, so it is considered as a possible burden to the kidneys. Those 50kg people have to eat 1 kg chicken breast every day to reach this amount. Obviously, most people can't eat this amount. Moreover, the daily intake of protein by bodybuilders is more than three times that of ordinary people, and no research shows that bodybuilders have kidney problems. People who exercise regularly usually consume more protein than ordinary people.
Therefore, in people with normal renal function, high protein has no harm to the kidneys. But if there are already kidney diseases, such as chronic nephritis, it needs to be controlled. In addition, some people say that the purine in meat, especially seafood, is relatively high and it is easy to get gout. In fact, it is also the case. Gout patients need to control their diet, and normal people have no problem.