There are many reasons for hair loss: 1, seborrheic alopecia: it is more common in young adults, showing that the scalp oil secretion is thick, the hair is bright, sparse and sparse, or the hair is dry, dandruff is more, dull and thin. Solution: Pay attention to light diet, eat less irritating food, eat more fruits and vegetables or take vitamins B6 and B2 orally. 2, pathological alopecia: mainly due to viruses, bacteria, high fever damage hair mother cells, inhibit the normal division of hair mother cells, so that hair follicles are in a state of shock and lead to hair loss, such as acute infectious diseases, long-term use of certain drugs and so on. Solution: Take more rest, and your hair will grow back after recovery or withdrawal. 3, chemical hair loss: harmful chemicals damage scalp tissue, hair follicle cells lead to hair loss solution: do not use irritating hair dyes, perms and inferior shampoo. 4, physical hair loss: hair loss caused by air pollutants blocking hair follicles, harmful radiation and other reasons. Solution: Don't use nylon comb and nylon head brush which are easy to generate static electricity, wear protective cap in the environment with serious air dust pollution and wash your hair in time. 5, nutritional hair loss: malnutrition caused by digestive and absorption dysfunction leads to hair loss solution: strengthen nutrition, eat more fruits and vegetables, kelp, mulberries, walnuts. 6, obesity and hair loss: a large number of saturated fatty acids produce waste after metabolism in the body, blocking hair follicles and causing hair loss. Solution: eat less greasy food and strengthen physical exercise. There is also hereditary alopecia, and there is no effective method at present.