Recently, I have seen more and more people with hair loss in my clinic, both men and women, with seborrheic alopecia being the main cause of all kinds of hair loss. What are the factors that cause hair loss? Normal people lose about 50-80 hairs per day on average, which is a normal metabolism, and the number of hairs shed per day is roughly the same as the number of new hairs, so it does not become thinner. If the number of hair loss exceeds this number, and the hair is significantly thinner than before that is pathological hair loss, if the usual hair loss is not much, but the hair growth is very slow, hair thinning, this also belongs to pathological hair loss. Hair growth is divided into 3 phases, anagen phase, regression phase and resting phase, generally the anagen phase 2-5 years, regression phase a few days, resting phase about 3 months. A. The causes of hair loss are as follows: 1. Endocrine disorders. Hair loss is related to the increase of androgens in the human body. Dihydrotestosterone is one of the main androgens in the human body, mainly in the blood, because the nutrition of the hair to provide through the blood, so the increase of dihydrotestosterone in the blood will continue to affect the hair follicles, so that the hair follicles gradually atrophy, apoptosis, our hair will become more and more thin and soft, the formation of seborrheic alopecia. Another scholar found that there are many patients suffering from thyroid disease combined with hair loss, so hair loss is also related to thyroxine. 2, mental and nervous disorders. Some young people have hair loss due to high work and life stress or long-term mental tension and depression. 3, genetic. Alopecia areata patients with family history accounted for 20%. In heredity, dominant heredity for men and recessive heredity for women, which is one of the reasons why there are more men than women with hair loss. 4. Immune dysfunction. Clinically, it is found that people with immune system disorders such as lupus erythematosus and ulcerative colitis are often accompanied by hair loss. 5, lesion infection. Infection caused by microorganisms can lead to hair follicle necrosis and hair loss. 6, improper diet and fat metabolism disorders. Some young people like to eat meat and alcohol excessively, when the body produces a lot of cholesterol can make too much sebum, which affects the blood supply of hair follicles. Impede the normal growth of hair and cause hair loss. 7, blood deficiency and kidney deficiency. Chinese medicine believes that hair loss is the result of blood deficiency and kidney deficiency. 8, hair damage. Foreign experts have pointed out after investigation, long-term use of hair dyes, hair loss can occur in 2 to 20 years. In addition, the frequent use of hair dryers, fire pliers, electric heaters perm, can also cause hair loss. Second, in order to prevent hair loss to develop some of the following good habits: 1, no nylon combs and head brushes. Because nylon combs and head brushes are prone to static electricity, will bring bad stimulation to the hair and scalp. The ideal is to use boxwood combs and pig bristle head brush, not only to remove dandruff, increase hair luster, but also massage the scalp, promote blood circulation. 2, moderate shampooing. It is not advisable to shampoo too often, and at the same time need to rub while massaging, not only to keep the scalp clean, but also to increase the blood supply to the scalp. Of course, if the hair greasy should be diligent washing. 3, do not use a strong degreasing or alkaline shampoo. These shampoos are very strong degreasing and dehydration, easy to make the hair dry scalp necrosis. You should use a natural shampoo that is not irritating to the scalp and hair, or according to your hair quality. 4, pay attention to nutrition. Eat more vegetables and fruits, eat less stimulating food, and take more vitamin classes. Of course if hair loss has occurred it is best to see a dermatologist in a timely manner. The first thing to distinguish is that type of hair loss, so that you can treat the symptoms.