Skin cancer risk factors: sun, tanning beds, moles and skin type

The main types of skin cancer

Skin cancer is the most common cancer in the United States (NCI PDQ). The two most common types are basal cell carcinoma and squamous cell carcinoma, together called nonmelanoma skin cancer (or keratinocyte carcinoma). Nonmelanoma skin cancer can usually be cured. Melanoma, which forms in the cells that give skin its color, is less common but grows and spreads quickly and can be harder to cure (NCI PDQ). Skin cancer can appear anywhere on the body, but it is most common on skin that gets sun, such as the face, neck, hands and arms (NCI PDQ).

The main cause: ultraviolet (UV) light

UV radiation is the invisible energy in sunlight. Sunlamps and tanning beds give off UV radiation too (NCI PDQ). The NCI lists being exposed to UV, and how sensitive your skin is to it, as risk factors for skin cancer (NCI PDQ). The USPSTF adds that exposure in childhood and the teen years raises the risk later in life, especially with bad sunburns (USPSTF 2018).

Risk factors for basal and squamous cell skin cancer

The NCI lists these risk factors for nonmelanoma skin cancer (NCI PDQ):

• Natural sunlight or artificial sunlight (such as from tanning beds) over long periods of time
• A fair complexion: fair skin that freckles and burns easily, does not tan or tans poorly; blue, green or other light-colored eyes; red or blond hair
• Actinic keratosis (rough, scaly patches caused by sun damage)
• Past treatment with radiation
• A weakened immune system, including people who take medicine to hold the immune system back after an organ transplant
• Exposure to arsenic

Risk factors for melanoma

The NCI lists these risk factors for melanoma (NCI PDQ):

• A fair complexion (as above)
• Natural or artificial sunlight (such as from tanning beds) over long periods of time
• Many blistering sunburns, especially as a child or teenager
• Many moles (also called nevi)
• A family history of unusual moles (atypical nevus syndrome)
• A family or personal history of melanoma
• Being White

Fair skin raises the risk, but people of all skin colors can get skin cancer (NCI PDQ). MedlinePlus sums up who is more likely to get skin cancer: people who spend a lot of time in the sun or have been sunburned, have light-colored skin, hair and eyes, have a family member with skin cancer, or are over age 50 (MedlinePlus).

Which ones you can change

What sun protection can and cannot promise

The NCI is careful here. Sunscreen has been shown to prevent sunburns and actinic keratoses, which can turn into squamous cell carcinoma (NCI PDQ). But not enough studies have been done to prove that staying out of the sun, sunscreen or protective clothing lowers the risk of nonmelanoma skin cancer, and it has not been proven that sunscreen protects against melanoma (NCI PDQ). Even so, skin experts suggest (NCI PDQ):

• Using sunscreen that protects against UV radiation
• Limiting time in the sun, especially when the sun is strongest
• Wearing long sleeve shirts, long pants, sun hats and sunglasses outdoors

The USPSTF counseling advice names broad-spectrum sunscreen with SPF 15 or higher, hats, sunglasses or sun-protective clothing, seeking shade during midday hours (10 am to 4 pm), and avoiding indoor tanning (USPSTF 2018). One caution from the NCI: people who use sunscreen to avoid burning may stay in the sun too long (NCI PDQ). The skin cancer prevention check shows whether the USPSTF advises sun protection counseling for your age and skin type.

Warning signs on a mole: ABCDE

Often the first sign of melanoma is a change in the size, shape, color or feel of a mole. Melanoma may also appear as a new mole. MedlinePlus suggests thinking of ABCDE (MedlinePlus):

• A, asymmetry: the shape of one half does not match the other
• B, border: the edges are ragged, blurred or irregular
• C, color: the color is uneven and may include shades of black, brown and tan
• D, diameter: there is a change in size, usually an increase
• E, evolving: the mole has changed over the past few weeks or months

Have a doctor check any suspicious skin markings and any changes in how your skin looks. Treatment is more likely to work well when cancer is found early (MedlinePlus).

What the USPSTF says about skin checks

The 2023 screening statement does not apply to people with a personal or family history of skin cancer, people with changing or irregular moles, or people already followed for a high risk (USPSTF 2023). The skin cancer screening check walks through it, and screening tests by age lists the other checks for your age.

Common questions

Can people with dark skin get skin cancer?

Yes. A fair complexion raises the risk, but people of all skin colors can get skin cancer (NCI PDQ).

Does sunscreen prevent skin cancer?

It prevents sunburn and actinic keratoses (NCI PDQ). Studies have not yet proven that it lowers the risk of skin cancer itself, so skin experts pair it with shade, clothing and less time in strong sun (NCI PDQ).

Are tanning beds safer than the sun?

No. Tanning beds and sunlamps give off UV radiation, and the NCI lists artificial sunlight from tanning beds as a risk factor for both nonmelanoma skin cancer and melanoma (NCI PDQ).