Four major fishes refer to artificially raised herring, grass carp, silver carp and bighead carp, and hair products refer to foods rich in nutrition or irritating, which are particularly easy to induce certain diseases (especially old diseases) or aggravate existing diseases. The four big fish are artificially reared freshwater fish, with tender meat, delicious taste and rich nutrition, which is one of the common delicacies on the table of China people.

It should be noted that although the four big fish do not belong to hair, for some people, such as allergic people and gout patients, they also need to eat in moderation or avoid eating.