But they are also commonly found on the face, arms and legs. Moles can be present in more obscure locations as well including on the scalp, under the nails, in the armpits or around the genitals. Most of us have from 10 to 40 moles. The number of moles you have may constantly change. New moles may appear up until age 40, but most appear by age 20.
Some moles disappear with advancing age.
It's especially important to become familiar with the moles on your skin because, in rare cases, they can become cancerous. Monitoring your moles and other pigmented patches, such as freckles or age or liver spots, is an important first step in reducing your risk of skin cancer especially malignant melanoma, which begins in or near a mole or other dark spot on the skin. Cancer Center Signs and Symptoms Moles come in a wide variety of colors, shapes and sizes. They can be flesh-colored, brown, blue or black spots that vary in shape from oval to round, and from the size of a pinhead or pencil eraser to large enough to cover an entire limb. Moles that are larger than 8 inches in diameter and present at birth are a special problem.