It is caused by obstruction of the fine circulation between tissue cells, cell lysis and death, and increased melanin to form pigmentation. The epidermis of the face is the thinnest, the capillaries are the most abundant, and the pigmentation is most likely to form. The pigmentation is the main part In the basal layer of the epidermis, melanin particles increase significantly. In severe cases, there are more melanin in the melanocytes of the dermis. Compared with normal, the number of pigment cells, the formation of melanin and the activity of melanin particles all increase differently.
(1) Yin-yang imbalance in the human body, firstly due to stagnation of liver qi, resulting in blood stasis facial; secondly, weak spleen and stomach, qi and blood can not moisturize the face, damp heat rises to the formation of spots on the face; thirdly due to insufficient kidney yang, yang disperse, blood stasis facial formation chloasma.
(2) After pregnancy, the placenta secretes more androgen and progesterone, so symmetrically distributed chloasma is common on the cheeks of women during pregnancy. However, after the secretion of androgens and progesterone in the body returns to normal after delivery, most people's spots will naturally decrease or disappear.
(3) Drug factors. 9% to 20% of women who take long-term oral contraceptives are prone to chloasma. Some people have facial spots even one month after oral contraceptives. In addition, they take drugs for high blood pressure, diabetes and polyphagia. Strong foods, such as celery, coriander, carrots, etc. are also easy to cause melasma.
(4) Some chronic diseases such as chronic hepatitis and tuberculosis will increase the activity of tyrosinase and increase the production of melanin, but the body's ability to eliminate melanin will be weakened. Once melanin cannot be excreted from the body in time, it will also be produced on the face over time Melasma; In addition, improper use of cosmetics can aggravate and accelerate