Many moles that develop during adulthood are related to sun exposure and effects on melanin production. They are often benign, but some changes can indicate cancer.

A mole, or nevus (plural: nevi), is an area of growth on the skin. Some moles (nevi) are present at birth, while others develop throughout your lifetime.

While mostly thought of as brown, moles can come in various colors, including red, pink, flesh-colored, tan, almost black—even blue and white. Some may also have long hair or a fine down. Most moles are benign, but it’s still important to monitor them for any changes that could indicate cancer growth.

Three main types of moles include:

Congenital moles

Congenital moles are present at birth and affect about 1 out of every 100 babies, according to the American Osteopathic College of Dermatology (AOCD). They can be flat and vary in color, but most don’t become cancerous. Types can include:

  • congenital nevus, which are present at birth and often benign; a larger size may be more likely to become cancerous later in life
  • blue nevi, which are blue-gray or blue-black moles and are classified as common or cellular blue nevus

Acquired moles

Acquired moles develop later in life. Most of these are a shade of brown and appear due to sun damage.

They’re typically round and do not change significantly as you age. These types of moles can darken over time and will not necessarily turn into melanoma. In people with olive or dark skin, they tend to show up on the face, ears, and extremities, presenting as a diffuse pattern that contains darker areas, according to 2015 research.

Types of acquired moles can include can include:

  • compound nevi, which are raised moles and usually skin-colored
  • intradermal or dermal nevi, which are raised, dome-shaped moles that are typically the color of your skin
  • junctional melanocytic nevi, which typically appear during childhood as flat moles with a uniform color that can range from brown to black
  • seborrheic keratoses, which are raised benign growths that can be dark in color and rough to the touch
  • spitz nevi, which are raised bumps that can be pink, red, blue, black, or skin-colored

Atypical moles

Unlike congenital and acquired nevi, atypical moles are at a greater risk of becoming cancerous. The AOCD estimates that 1 in 10 people in the U.S. has at least one atypical nevus.

Atypical moles are slightly larger than acquired moles and have irregular-shaped borders. They tend to feature a mixture of colors, including tan, brown, black, pink, and white. They are also a risk factor for melanoma, which can be equally colorful but darker as a rule, even glossy black. Atypical moles can include dysplastic nevi and Clark’s nevi.

The American Academy of Dermatology Association (AAD) recommends using the acronym ABCDEs of melanoma to remember concerning symptoms and features of a potentially cancerous mole:

  • Asymmetry: The mole is not uniform, with one half not like the other.
  • Border: The mole has an irregular or poorly defined border.
  • Color: The mole varies by shade or color within the same mole.
  • Diameter: The mole grows to 6mm (about 1/4 inch) or larger.
  • Evolving: The mole changes in size, shape, or color.

Learn more about what melanoma looks like.

If you develop a new mole or have concerns about an existing mole, especially one that has changed or grown, it is best to make an appointment with a dermatologist.

Moles occur due to abnormal growth in the skin cells. However, abnormal growth doesn’t always mean cancer.

Some people are born with moles, as with congenital nevi. You can also develop moles during childhood and early adulthood. These moles can become lighter or darker as you age.

Other factors like sun exposure or certain medications can contribute to the darkening or developing of moles.

You might decide to have a mole removed for a variety of reasons.

Some moles may bother you because of their size or location. Others may need to be removed because your dermatologist is concerned about melanoma. No matter what, you should never try to remove a mole on your own. This can potentially lead to infection, and if the mole is cancerous, you may miss an opportunity for an earlier diagnosis.

Atypical moles are generally considered precancerous, but most of these moles don’t turn into cancer.

When a dermatologist removes a mole, they will typically shave it (smaller moles) or surgically excise it (larger ones or those that are cancerous). Depending on how large the mole is, stitches may be necessary to seal the area afterward. It can take two appointments to completely remove a mole.

Here’s how typical moles look compared to atypical moles.

A mole removal treatment may leave some scarring. Scars may be treated with chemical peels, laser treatments, and other methods to lessen pigmentation after healing.

A dermatologist may recommend methods to reduce the appearance of scarring.

Keep an eye out for signs of a mole returning after it has been removed. While it may not necessarily be cancerous, the risk of melanoma can be greater if the original mole had cancer cells.

Doing monthly self-checks can help you notice changes that may need a dermatologist’s attention.

Dermatologists generally recommend that all adults get an annual skin checkup—at least by their early 20s, and before then if they are fair-skinned. This allows them to examine a person’s existing moles for changes and potentially cancerous growths. But if you spot any concerning changes to your skin between checkups, they often recommend you make another appointment.

Some changes that warrant a checkup include:

Skin care is important to your overall health, and it’s worth keeping in mind that moles are a part of your skin, too.

The American Cancer Society recommends full sun protection regularly for everyone, regardless of skin color.

Wearing sunscreen with SPF 30 or higher daily can help protect your skin, including any moles, from sun damage. You may also want to wear a hat when outdoors or seek shade, especially when the sun is high in the sky.

While people with fair skin have a higher risk of skin cancer, people of all skin colors and ethnicities are at risk for developing skin cancer.

Due to misconceptions and other factors, people of color are more likely to receive a delayed skin cancer diagnosis when the cancer is more advanced and harder to treat.

The ADD notes that skin cancer is more likely to show up in specific ways on skin of color. This can include showing up in places that do not get a lot of sun exposure, such as:

  • between the toes
  • on the bottoms of the feet
  • on the palms of the hands
  • around the anus or genitals

People of color are more likely to develop acral lentiginous melanoma (ALM), a rare melanoma subtype. ALM is predominantly found under the nails, on the palms of the hands, and under the soles of the feet.

Skincare where a mole used to be

If you’ve had any moles removed, it’s important to give the remaining skin some extra TLC. Sunscreen can help prevent scars from darkening and becoming more noticeable.

Keep scars clean and moisturized. If the area is still healing, protect it by using petroleum jelly. Once your skin has healed, massage your scar to help flatten and smooth out the surface.

What happens if you pick a mole off?

Cutting or picking off any skin growth can leave a permanent scar and carries a high risk of infection. Only medical professionals should carry out a mole removal.

How do you get rid of skin moles?

Medical professionals can shave off smaller moles. They may carry out a surgical excision for larger moles.

What do cancerous moles look like?

Cancerous skin growths are typically larger than 1/4 inch in diameter, have irregular borders, and may appear raised and discolored.

Are moles a form of cancer?

Moles are not a form of cancer. However, skin cancer can produce skin growths that resemble moles.

Moles, or nevi, are a common occurrence. They’re more likely to develop in later childhood and adulthood, though you can be born with moles, too.

Most moles do not become cancerous—but when they do, they can be life threatening if not caught early. Knowing your skin and doing self-checks can help.

See a dermatologist regularly for checkups and notify them of any sudden changes to your skin.