FAQ Frequently Asked Questions

Moles are formed by clusters of melanocytes—cells that produce melanin. Some are present at birth, while others develop later in life; factors such as ultraviolet (UV) rays, skin irritation, and hormonal influences are believed to play a role. Since the way moles form varies from person to person, it is not possible to determine the cause based on appearance alone.

Moles include simple naevi, which are usually flat and measure about 1 to 2 mm, and melanocytic nevi, which can range from flat to raised. Their color also varies from light brown to black. Since it is impossible to determine the type based on appearance alone—and because there are other lesions that may look like moles—it is important to have any concerning changes examined by a doctor.