The most common type of cancer in the United States is skin cancer. But, in many cases, this type of cancer is preventable. Understanding what can and can’t cause skin cancer can help you take important preventive measures.

In this article, we’ll discuss the most common causes of skin cancer as well as some things that haven’t been determined to cause it. We’ll also take a look at the warning signs that may be a signal to see your doctor.

When DNA gets damaged, it can cause abnormalities in cells. As a result, these cells don’t die off as they should. Instead, they continue to grow and divide, creating more and more abnormal cells.

These mutated cells are able to evade the immune system and eventually spread throughout the body. When this DNA damage starts in your skin cells, you have skin cancer.

Types of skin cancer include:

About 95 percent of skin cancers are basal cell or squamous cell. These nonmelanoma types are quite curable when diagnosed and treated early. It’s hard to say how many people get these types of cancer since there’s no requirement to report them to a cancer registry.

Melanoma is more serious, accounting for about 75 percent of skin cancer deaths. According to the American Cancer Society, there were more than 96,000 new cases of melanoma in 2019.

Sun exposure

The No. 1 cause of skin cancer is ultraviolet (UV) radiation from the sun. Here are some important things to keep in mind:

  • Eighty percent of sun exposure occurs before you reach age 18.
  • Exposure in winter is just as risky as exposure in summer.
  • Nonmelanoma skin cancer can result from cumulative sun exposure.
  • Severe sunburns before age 18 can lead to melanoma later in life.
  • Some medications, such as antibiotics, can increase your skin’s sensitivity to sunlight.
  • Getting a “base tan” offers no protection from sunburn or skin cancer.

You can lower your sun exposure by doing the following:

  • Use sunblock or protective sunscreen with SPF 30, at minimum.
  • Wear protective clothing when in the sun.
  • Seek shade when possible, especially between 10 a.m. and 3 p.m. when the sun’s rays are strongest.
  • Wear a hat to protect the skin on your face and head.

Tanning beds

UV rays can damage your skin, no matter where they come from. Tanning beds, booths, and sunlamps produce UV rays. They’re no safer than sunbathing, nor do they prepare your skin for suntanning.

According to research, indoor tanning is considered carcinogenic to humans. Research has also shown that tanning beds increase the risk of melanoma even if you don’t burn.

Genetic changes

Genetic mutations can be inherited or acquired during your lifetime. The most common acquired genetic mutation associated with melanoma is the BRAF oncogene.

According to the National Cancer Institute, about half the people who have melanoma that’s spread, or melanoma that can’t be removed with surgery, have mutations in the BRAF gene.

Other gene mutations include:

  • NRAS
  • CDKN2A
  • NF1
  • C-KIT

Less common causes

If you get your nails done at a salon, chances are you’ve put your fingers under UV light to dry.

One very small study published in JAMA Dermatology suggests that exposure to UV nail lights is a skin cancer risk factor. While further research is needed, study authors recommend using other options for drying your nails.

Other less common causes of skin cancer include:

  • repeated exposure to X-rays or CT scans
  • scars due to burns or disease
  • occupational exposure to certain chemicals, such as arsenic

Tattoos

There’s no evidence that tattoos cause skin cancer. However, it’s true that tattoos can make it harder to spot skin cancer early on.

It’s best to avoid getting a tattoo over a mole or other spot that may be of concern.

Check your tattooed skin periodically. See a dermatologist right away if you see anything suspicious.

Sunscreen

It’s wise to consider the ingredients of any product you put on your skin, including sunscreen. But experts at MD Anderson Cancer Center and Harvard Medical School say there’s no evidence that sunscreens cause skin cancer.

Along with the American Cancer Society (ACS), the experts recommend the use of broad-spectrum sunscreen that blocks out both UVA and UVB rays.

Cosmetics and skin care products

Many cosmetic, skin care, and other personal care products have long lists of ingredients. Some of these ingredients may be harmful in large quantities.

For the most part, though, cosmetics and personal care products don’t have high enough levels of certain toxic ingredients to cause cancer.

According to the ACS, there haven’t been enough long-term studies in humans to make claims about cancer risk. But, the health risks of long-term exposure to certain toxins can’t be ruled out completely.

If you have concerns about a product you’re using, check the ingredients and consult with a dermatologist.

Anyone can develop skin cancer, but certain factors can increase your risk. This includes:

  • having fair skin or freckled skin
  • having had at least one severe, blistering sunburn, especially as a child or teen
  • long-term exposure to the sun
  • tanning beds, booths, or lamps
  • living in a sunny, high-altitude climate
  • moles, especially abnormal ones
  • precancerous skin lesions
  • family history of skin cancer
  • weakened immune system
  • exposure to radiation, including radiation therapy for skin conditions
  • exposure to arsenic or other occupational chemicals
  • xeroderma pigmentosum (XP), a condition caused by an inherited genetic mutation
  • certain inherited or acquired genetic mutations

If you’ve had skin cancer once, you’re at risk of developing it again.

Melanoma is most common in non-Hispanic whites. It’s more common in women than men before age 50, but more common in men after age 65.

See your doctor if you notice a change to your skin, such as a new skin lesion, new mole, or changes to an existing mole.

Basal cell carcinoma can appear as:

  • a small, waxy bump on the face or neck
  • a flat pinkish-red, or brown lesion on the arms, legs, or trunk

Squamous cell carcinoma may look like:

  • a firm, red nodule
  • a rough, scaly lesion with itching, bleeding, or crusting

Melanoma may look like a bump, a patch, or a mole. It’s typically:

  • asymmetric (one side is different from the other)
  • ragged around the edges
  • uneven in color, which may include white, red, tan, brown, black, or blue
  • growing in size
  • changing in appearance or how it feels, such as itching or bleeding

The leading cause of skin cancer is sun exposure. Exposure in childhood can lead to skin cancer later in life.

While there are certain risk factors that we can’t help, like genetics, there are steps you can take to lower your risk of skin cancer. This includes protecting your skin from UV rays, avoiding tanning beds, and using broad-spectrum sunscreen

See your doctor if you notice any unusual changes to your skin. When detected early, skin cancer is curable.