The overall nutritional value of fish is very high. As the name implies, the biggest difference between river fish and sea fish lies in the growing environment. In fact, strictly speaking, river fish should be called freshwater fish. Common fish are carp, crucian carp, grass carp, silver carp, Wuchang fish, tilapia and eel. Marine fish include hairtail, tuna, large yellow croaker, small yellow croaker, Spanish mackerel, salmon and turbot.

Whether freshwater fish or marine fish, their nutritional components are basically the same, and their total nutritional value is very high. First of all, fish is rich in protein, and the quantity and proportion of essential amino acids are most suitable for human needs, which is a good source for human to ingest protein. Secondly, fish contains less fat and is mostly composed of unsaturated fatty acids. The absorption rate of human body can reach 95%, which has the functions of lowering cholesterol and preventing cardiovascular and cerebrovascular diseases. Thirdly, fish is rich in minerals such as iron, phosphorus and calcium. Fish liver contains a lot of vitamin A and vitamin D.

In addition, the muscle fiber of fish is very short and has high water content, so the meat is tender and easier to absorb than the meat of livestock and poultry. Fish is more beneficial to people's health than food with high nutritional value but not easy to absorb.

Marine fish contain essential nutrients for the brain.

Common marine fish include hairtail, yellow croaker, abalone, squid, sardine, pomfret (flat fish), Spanish mackerel, tuna, salmon (salmon) and so on. According to experts, the liver oil and body oil of marine fish contain a highly unsaturated fatty acid that is not found in land animals and plants, which contains a component called DHA, which is an essential nutrient for the brain. It can be said that DHA is very important to improve people's memory and thinking ability from the fetus, from infants to teenagers, and even in the whole life activities.

In addition, omega-3 fatty acids and taurine in marine fish are much higher than those in freshwater fish. It is found that omega-3 fatty acids have a good effect on relieving cerebral vasospasm and malignant migraine, and can also improve the anti-inflammatory ability of the body.

Marine fish is slightly superior in nutrition and taste.

Similar nutritional components do not mean that the nutritional value of the two is exactly the same. Marine fish has more nutrients than river fish, and its nutritional value is slightly better.

Seawater is extremely rich in nutrients, especially a lot of nutrients, which makes the contents of minerals and vitamins in marine fish higher. In addition, the liver oil and body oil of marine fish contain a highly unsaturated fatty acid that is not found in land animals and plants, and it contains a component called DHA (commonly known as brain gold), which is an essential nutrient for the brain and is very important for improving memory and thinking ability. In addition, the contents of omega-3 fatty acids and taurine in marine fish are much higher than those in freshwater fish, which has protective effects on the heart and brain.

In terms of taste, sea fish tastes fresher than river fish. This is because the swimming range and swimming strength of marine fish are larger than those of river fish, which makes their muscles more elastic and delicious. On the other hand, river fish taste earthy because they grow in water with more humus. Such an environment is suitable for the reproduction and growth of actinomycetes. Bacteria invade fish blood through gills and secrete a brown substance with earthy smell, which is difficult to remove during cooking.