When you remove underarm hair, your skin gets damaged and can react by producing an extra pigment, called melanin. This can lead to the appearance of dark marks on your underarm skin. Dove has the answer with this night treatment, which contains advanced nourishing moisturisers and the proprietary true tone complex - 12-HSA, Vitamin C and Vitamin B3 - which targets dark marks for more even skin tone. During the night, your skin is actively repairing itself and is more receptive to treatment. The underarm dark mark eraser works in sync with your skin's night time natural cell renewal cycle to help reduce the appearance of your underarm dark marks.