Newswise — It’s all fun in the sun until you realize you should have reapplied more sunscreen. Sunburns are no fun, but more importantly, they are dangerous. This reddening of your skin caused by overexposure to the sun’s ultraviolet (UV) radiation may seem like just a temporary irritation—but it can cause long-lasting damage.

Overexposure to the sun can result in:

  • Pre-cancerous and cancerous skin lesions due to decreases in the skin's immune function
  • Mottled pigmentation, or discolored areas of the skin
  • Sallowness, or a yellow discoloration of the skin
  • Telangiectasias, or the dilation of small blood vessels under the skin
  • Elastosis, or the destruction of the elastic and collagen tissue

“The sun's UV rays damage the DNA in the cells of your skin,” says Suzanne Olbricht, MD, Chief of Dermatology at BIDMC. “These harmful DNA changes can be quite profound and you will sometimes see the damage in the form of peeling skin.”

Olbricht also notes that although your skin recovers when you are young, extended UV radiation can damage the cellular mechanisms that repair DNA. “That's why the older you get, the more aged your skin looks, and the more skin cancers you may have,” she says. “Your repair mechanisms are damaged—so just a little bit more sun can really affect your skin’s ability to repair itself.”

All skin types can burn. Melanin, the component in your skin that determines pigment, plays a large role in natural skin protection from the sun’s UV rays. “The darker one’s skin, the more melanin is present and therefore the greater the UV protection,” Olbricht says. “But no matter the color, your skin can burn. Everyone should take precautions when heading out into the sun.”

Here are a few tips to help avoid sunburns:

Be choosy with your sunscreen.
Look for a broad spectrum sunscreen, which protects against all types of harmful rays, and one with a strong sun protection factor (SPF). “SPF measures how well the sunscreen protects your skin compared to if you were not wearing it,” Olbricht says. “For example, if it normally takes 20 minutes for your skin to turn red, a product with SPF 15 will typically prevent sunburn 15 times longer.”

Apply sunscreen generously and reapply regularly.
For the best protection, you typically need one ounce, or a shot glass full, of sunscreen to cover your entire body, including your face, ears and scalp. “A rule of thumb for reapplying is every two hours,” Olbricht says. “But if you’re swimming or sweating a lot, you will want to reapply more often.”

Avoid peak hours in the sun.
The sun’s rays are the strongest between the hours of 10 a.m. and 2 p.m., meaning your skin is most susceptible to burning. Seek shade during these peak hours.

Wear protective attire.
Sunglasses with UV protection, a wide-brimmed hat, and clothing with UPF protection (ultraviolet protection factor) will help protect you from the sun. “A lot of children’s summer clothing and swim attire can be found with UPF 50+, which helps block 98% of UVA/UVB rays,” Olbricht says.

Perform your own skin checks and get your skin checked regularly by your doctor.
A self-exam of your skin once a month will help you keep track of any irregularities. Learn the pattern of any moles, blemishes or freckles so that you will notice any changes. “Most people have moles, and almost all are harmless,” Olbricht says. “But it is important to recognize changes in a mole, such as its size, shape or color. If you notice changes, call your primary care doctor or dermatologist for a checkup.”

Learn about the Department of Dermatology at BIDMC.