The normal color of human finger (toe) nails is light red and lustrous. If the human physiological function is disturbed, leading to the occurrence of diseases or malnutrition, trauma, infection, poisoning, application of drugs or changes in the environment and life, the color of finger (toe) nails may change. What are the causes of finger (toe) nail color changes? Dr. Fox, a spokesperson for the American Academy of Dermatology, has confessed that danger warning signs of diseases such as hepatitis, fungal infections, lupus, heart disease, and anemia can appear on the nails. For example, lupus patients have angular blood vessels in the nail folds; 10% of psoriasis starts with the nails and causes splitting and depression of the nail bed; obsessive-compulsive neurosis is manifested by chronic nail biting or digging; even common disorders, such as thyroid disease, can cause abnormalities in the nail bed, which is dry, fragile and prone to cracking. 1, nails are stained A person suffering from chronic diseases, long-term emotional depression, smoking, or finger contact with copy paper, hair dye and other chemical stains can make the nails discolored or stained. If the nail is deeply stained, it is better to wait until a new nail grows out. If you want to get rid of the surface stain in time, you can use a slice of lemon to rub your fingertips repeatedly, and then clean and dry them. 2, nails look strange If you lack protein or iron for a long time, it is usually easy to cause spoon or flat nails, which can be corrected by improving diet and nutrition. It is said that wearing artificial nails can help nails store moisture and become soft, causing nails to bend upward, this problem should be increased nutrition as appropriate, remove the artificial nails worn. 3, nail luster If the nails are wavy and lusterless, it may reveal a lack of protein, lack of vitamins A and B or reveal a mineral deficiency. This can be addressed by improving your daily diet and taking a daily multivitamin supplement. Adding vitamin B6 and 15 grams of zinc is sufficient. If the nails are all white, it may indicate a liver disorder, which can be treated by an internist. 4. Pale nails This may be a sign of zinc deficiency and vitamin B6 deficiency, or may be caused by anemia. If the symptoms of pale nails persist even after improving the nutritional status of the diet, it is time to seek medical advice to find out the cause. 5. Dents in the nails This kind of nail disease indicates a lack of calcium, protein, and sulfur in the body, which can be obtained from eggs and garlic, and should be consumed regularly.