Skin spots may be related to external factors, age factors, endocrine disorders and so on. 1. External factors: When exposed to sunlight for a long time, it will easily cause burns to the skin caused by ultraviolet rays, which will activate melanocytes in the epidermis, prompting the formation of melanin and the phenomenon of skin spots. 2. Age factor: when the function of various tissues and organs in the body gradually decreases with the growth of age, the function of black cells becomes abnormal, which will easily lead to the increase of melanin synthesis, resulting in the occurrence of skin spots. 3. Endocrine disorders: If you stay up late for a long time and live a stressful life, it may lead to endocrine disorders of the human body, which may cause slowing down of blood circulation and poor metabolism of the body, resulting in precipitation of melanin, leading to the phenomenon of skin spotting. When skin spots appear, you should immediately go to the dermatology department of regular hospitals, and standardize the treatment under the guidance of doctors.