Recurrent episodes of seborrheic dermatitis do not usually lead to melanin deficiency in the skin. Melanin deficiency is considered to be related to congenital and acquired factors. Seborrheic dermatitis is a common chronic inflammatory skin disease that occurs in newborns and adults. Seborrheic dermatitis recurrence is related to mental, dietary factors, vitamin deficiency. Recurrent episodes of seborrheic dermatitis may affect aesthetics, aggravate psychological burden, and increase the risk of infection. Seborrheic dermatitis may leave post-inflammatory hypopigmentation after cure, because when local inflammation occurs in the skin, there are lymphocytes, histiocytes and other infiltration at the site of inflammation, and these cells have the role of phagocytosis of melanin particles secreted by melanocytes, which makes the local skin color lighter, but generally does not lead to melanin deficiency. Melanin deficiency may be a defect in the function of melanocytes, which is common in congenital diseases and acquired diseases, the former is common in albinism, nevus without pigmentation, pemphigus, etc.; the latter is common in autoimmune melanin deficiency, which is mostly seen in vitiligo and other skin diseases. All of these diseases may lead to melanin deficiency. If seborrheic dermatitis is recurrent and there is a local lightening of the skin color, it is recommended to go to the dermatology department of the hospital for examination and standardized treatment under the guidance of the doctor.