Although the typical mole is a brown spot, moles come in a wide variety of colors, shapes and sizes:

  • Color. They're often brown, but moles can be tan, black, red, blue, pink, or flesh-colored.
  • Shape. They can vary in shape from oval to round.
  • Size. They can be as small as a pinhead or large enough to cover an entire limb. Generally, moles are less than 1/4 inch (about 6 millimeters) long — or smaller than the diameter of a pencil eraser.

Moles can develop virtually anywhere on your body, including your scalp, armpits, under your nails, and between your fingers and toes. Most people have between 10 and 40 moles, although the number you have may change throughout life. New moles can appear into midadulthood, and some moles may disappear as you age.

Varied surfaces

The surface of a mole can be smooth or wrinkled, flat or raised. Sometimes a mole may start out flat and brown and later become slightly raised and lighter in color. Some may become raised enough that they form a small stalk, which eventually may wear away. Others may simply disappear.

Although most moles appear during childhood and adolescence, they can continue to appear until midlife. There are also certain times in your life when moles are more apt to change; for example, they're likely to become darker, larger and more numerous because of hormonal changes that occur during adolescence or pregnancy.

When to see a doctor

If you're over 30 years old and a new mole appears, see your doctor. These signs and symptoms may indicate a medical concern:

  • Painful
  • Itching or burning
  • Oozing or bleeding
  • Asymmetry, when one half of the mole looks different
  • Suddenly different in size, shape, color or elevation, especially if part or all of the mole turns black

If you're concerned about any mole, see your doctor or ask for a referral to a dermatologist.

Dec. 06, 2011