Nickel has a wide range of sources, especially the nickel content in plant foods is higher than that in animal foods, such as loofah, mushrooms, eggplant, onion, bamboo shoots, kelp, cucumber, peas, lentils, green onions, soybeans, sesame seeds, spinach, tea and so on. However, there are many nickel contents in meat and seafood of animal foods, such as chicken, mutton, beef, crucian carp, yellow croaker, shrimp and shellfish. It should be noted that pregnant women and people who are allergic to nickel should avoid contact with nickel, otherwise it will affect the health of the fetus and themselves. Nickel absorbed from food is very little, and the small intestine is the main absorption site, and the absorption rate is very low. After absorption, it is excreted from feces and a small amount from urine. The total amount of nickel in human body is about 6 ~ 10 mg, which is widely distributed in organs and tissues such as bones, lungs, liver, kidneys and skin, among which the concentration in bones is relatively high.