The shark fin is not made to look like a fan, it is that it originally grows to look like a fan.

Shark fin is the short name of shark fin in folklore, also known as shark fin, shark shark shark fin, sand shark fin, gold silk vegetable, etc. It specifically refers to the fine filamentous cartilage in the shark's fins in the shape of vermicelli, and is made by drying the fins of sharks' pectoral, abdominal, and caudal fins. It is one of the famous traditional Chinese foods and one of the mountainous delicacies.

The reason why shark fins are edible is because the shark's fins contain a kind of fin tendon shaped like vermicelli, which contains about 80% of protein, and also contains fat, sugar and other minerals, but it is very difficult to be absorbed, so eat an egg to absorb more nutrients than the shark fins.

Nutritional Definition of Shark's Fin:

According to the Food and Nutrition Information Center, shark's fins don't contain a lot of nutrients. Most of what shark fins contain is cartilage tissue, with little to no vitamins.

Alternative medicine proponents argue that shark cartilage tissue contains anticancer substances, leading people to believe that eating shark fins will prevent them from getting cancer. But according to the National Cancer Institute, only one clinically randomized study in a peer-reviewed journal has examined whether shark cartilage tissue can be used in human cancer treatment, and the results show that shark fins don't have much effect.

Shark fins are like many other fish products in that they can contain high levels of mercury with a high risk factor. Mercury is mainly caused by marine pollution, and because sharks are at the top of the food chain, they end up containing higher levels of mercury than many other sea creatures. Therefore, shark fins are not as safe as we think.

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People's Daily News - Shark fins are actually not good for health