Eating fish allergy is a kind of protein allergy. Normal human intestinal digestive juice contains many digestive enzymes, such as protease and peptidase. Heterogeneous protein of aquatic fish is digested into peptides by protease, and then into amino acids by peptidase. protein molecules change from large to small, and the structure changes from complex to simple, and finally it is absorbed into the blood as a nutrient. Allergic people are allergic because intestinal digestive juice lacks some proteases or some peptidases, which can't fully digest foreign protein. People with allergies are advised to eat less spicy and seafood and fish.