There are many reasons why skin may darken over time. Here are the most common:
- Constricted Areas - Because the genitals, anal area and other intimate areas are poorly ventilated and constricted under clothing for the most part, they do not receive enough air circulation. This affects the color and texture of the skin. Wearing undergarments that allow air to circulate with clothing that allows the skin to breathe may help prevent some darkening.
- Hormones - As we age, hormonal changes cause private areas to become darker.
- Friction - Factors such as friction created during sex or exercise, by clothing or from body fat, affect the texture and color of skin.
- Sweat - Chemicals released from the body in the form of sweat also can play a role in darkening the skin. Since the areas of the genitals, anal area, breasts and underarms are constricted, sweat can remain on the skin for long periods of time causing the discoloration to occur.
- Pigment - The genital area has the highest density of melanocytes (cells that make pigment) than anywhere in the body. The denser the pigment, the darker the skin.