Protecting Your Skin From the Sun

Listen to the Cancer.Net Podcast: Protecting Your Skin From the Sun, adapted from this feature

The arrival of warmer weather usually means spending more time outdoors in the sun. However, no matter what time of year it is, it is important to protect your skin from the harmful ultraviolet (UV) radiation found in sunlight. Exposure to UV radiation is the number-one cause of skin cancer, which is the most common type of cancer diagnosed in the United States. Fortunately, most types of skin cancer can be prevented or successfully treated if they are found early.

UV radiation and skin cancer

There are two types of UV radiation: ultraviolet A (UVA) and ultraviolet B (UVB). UVB radiation causes sunburn and plays a role in the development of basal and squamous cell skin cancers and melanoma. UVA radiation penetrates the skin more deeply and contributes to premature aging of the skin and wrinkling. Doctors and researchers suspect that UVA also plays a role in the development of skin cancer, but it has not been proven yet.

People who live in areas with bright sunlight year-round or at high altitudes have a higher risk of developing skin cancer, as do those who spend a lot of time outside during the midday hours or in a tanning bed (which emits mostly UVA radiation).

People with fair skin, which has less pigment (melanin), have less protection against UV radiation. As a result, people with light hair and light-colored eyes who have skin that tans poorly or freckles, or people who burn easily, are more likely to develop skin cancer. 

Sun protection tips

Because most skin cancer is caused by excessive and unprotected exposure to UV radiation, here are a few simple steps you can take to help protect you and your family:

  • Use sunscreen every day, even if it’s cloudy. You should choose a broad spectrum sunscreen that protects against both UVA and UVB radiation, is water resistant, and has a sun protection factor (SPF) of 30 or higher. Other types of sunscreen may help prevent sunburn, but they will not protect against developing skin cancer.
  • Apply a generous amount of sunscreen (at least one ounce, enough to fill a shot glass) 15 to 30 minutes before going outdoors. Remember to reapply it every two hours or more often (every hour) if you are swimming or sweating. Also apply a lip balm or lipstick that contains sunscreen with an SPF of at least 30.
  • Sunscreen creams are better for dry skin, and gels are better for the scalp or hairy areas. If possible, avoid using sunscreen sprays. The U.S. Food and Drug Administration (FDA) has concerns that not enough sunscreen makes it onto the skin and that the spray may be inhaled into the lungs. However, always remember that preventing sunburns and skin cancer is the most important priority.
  • Sunscreen should be worn year round whenever you are outside. Do not use sunscreens if they have expired.
  • Be careful around water, snow, or sand. These surfaces reflect the damaging rays of the sun, which can increase the chance of sunburn.
  • Keep babies younger than 6 months old completely covered and in the shade. It is very important to protect young children from the sun because getting a bad sunburn during childhood increases a person’s risk of developing skin cancer as an adult.
  • Limit sun exposure between 10:00 AM and 4:00 PM, when the sun's rays are the most intense. Practice the shadow rule: if your shadow is shorter than you, the sun's rays are at their strongest, and you should find shade.
  • Protect your skin with a long-sleeved shirt, long pants, and a hat that shades the face, neck, and ears. Dark clothing with tightly woven fabric blocks more sun than white or loosely woven fabrics. For additional protection, look for clothing made with special sun-protective materials.
  • Wear sunglasses with 99% to 100% UV absorption to provide optimal protection for the eyes and the surrounding skin.
  • Pay attention to the UV index, which is often included in the weather report. This index is a relative measure of how damaging exposure to the sun will be on any particular day. The index is a scale of 1 to 10+. When the index is 10 or higher, people should stay indoors, if possible.
  • Be even more cautious if you are taking medications that may make you more sensitive to the sun, such as specific types of antibiotics, anti-inflammatories, antifungals, blood pressure medications, and chemotherapies.
  • Try not to rely on the sun to get your vitamin D. You can get enough vitamin D safely through a healthy diet that may include vitamin supplements.
  • Avoid tanning beds or sunlamps.

Early detection

Examining your skin regularly may help find skin cancer early, when there is the greatest chance it can be successfully treated. Perform an examination in front of a full-length mirror in a brightly lit room. It helps to have another person check the scalp and back of the neck.

With melanoma, the first sign is often a change in the size, shape, or color of an existing mole. It also may appear as a new or abnormal-looking mole. Most moles are not cancerous, but if you notice a mole that is changing, have it checked by a dermatologist (a doctor who specializes in diseases and conditions of the skin).

The "ABCDE" rule can help you remember these skin cancer warning signs:

Asymmetry: The shape of one half of the mole does not match the other.

Border: The edges are ragged, notched, or blurred.

Color: The color is often uneven with shades of black, brown, and tan. You may also see areas of white, gray, red, or blue.

Diameter: The diameter is usually larger than six millimeters (mm) (the size of a pencil eraser) or has grown in size.

Evolving: The mole has been changing in size, shape, color, appearance, or growing in an area of previously normal skin. Also, when melanoma develops in an existing mole, the texture of the mole may change and become hard, lumpy, or scaly. Although the skin may feel different and may itch, ooze, or bleed, melanoma usually does not cause pain.

Additionally, people at high risk for skin cancer should have their skin examined once a year by a dermatologist.

More Information

Guide to Skin Cancer (Non-Melanoma)

Guide to Melanoma

Additional Resources

American Academy of Dermatology: How do I prevent skin cancer?

FDA: Recommendations for Sunscreen

The Skin Cancer Foundation: Prevention Guidelines

U.S. Environmental Protection Agency: SunWise Program

Centers for Disease Control and Prevention: Skin Cancer Prevention.