First, pay attention to labor protection and avoid direct sunlight. Ultraviolet rays can promote melanocytes to produce melanin particles and make the skin black. It is best to apply some whitening sunscreen to the exposed parts.

Second, pay attention to diet, drink plenty of water, eat more fresh fruits and vegetables, inhibit the formation of melanin and ensure fair skin.

Thirdly, taking vitamin C orally can reduce dopaquinone to dopa, thus inhibiting the formation of melanin.