OHSU

Sunscreen Facts

Need for protection from sunlight

  • Exposure to both ultraviolet A (UVA) and ultraviolet B (UVB) rays results in cumulated damage that leads to skin aging, cataracts, corneal burns and the formation of skin cancer.
  • UVR penetrate deep into the skin support structure, affecting the skin's immune system and increasing cancer risks.
  • Eighty percent of lifetime exposure to sunlight occurs before the age 18.
  • UVA rays penetrate glass/windows.
  • Eighty percent of damaging rays can get through clouds.
  • Even one blistering sunburn in childhood could result in the development of melanoma later in life.
  • Sixty percent of the day's sunburning radiation occurs between the hours of 10 a.m. and 4 p.m.
  • Reflection from sand, water and white surfaces, such as a deck or bulkhead on boats, results in substantial UVR exposure.
  • Heat and brightness are not indicators of UV intensity.

How sunscreens and sunblocks work

  • Sunblocks (i.e., physical sunscreens containing zinc oxide or titanium oxide) reflect, scatter rays and act as a barrier to UVR.
  • Sunscreens (chemical) absorb UVA and UVB rays.
  • It has been determined microscopically that sun damage can be reversed by using sunscreens.
  • Sunscreens are labeled with a sun protection factor (SPF). For example, with an SPF 15 it takes 15 times as much sun exposure to get a sunburn as compared to no sunscreen at all.

Sunscreen application guidelines

  • Replace sunscreens yearly.
  • Cover all exposed surfaces, including tops of ears, scalps where there is thinning or no hair, noses and bony surfaces.
  • Water-resistant sunscreens lose their SPF after 40 minutes in water; waterproof sunscreens after 90 minutes. Re-apply as needed.
  • Apply sunscreen lip balm to lips.

Sunscreen for babies and infants

  • Avoid sun exposure, and do not use sunscreens on infants younger than 6 months.
  • Keep infants and young children out of the sun's peak rays.
  • Use umbrellas, canopies and wide-brimmed hats to stay in the shade.
  • When applying sunscreen, lightly rub sunscreen in your hands first, then apply to child's face.
  • Sunscreen sticks "stay put" more effectively and are less prone to get into eyes.
  • Use fragrance-free sunscreen to avoid attracting stinging insects.
  • For fidgety children, try spritz-on sunscreens.

Sunscreen for children

  • Children spend three times longer in the sun than adults.
  • Creams and lotions are less drying for young skin.
  • Set an example for your child by using sunscreens every day.
  • Children like sunscreen "glitter"; SPF is low, but better than no sunscreen at all.
  • Teaching children to put on sunscreen every day should be as important as teaching them to brush their teeth.
  • Select a product with a sun protection factor (SPF) 15 or greater; broad spectrum sunscreens protect best from UVA and UVB rays.
  • Apply sunscreens every day regardless of the season.
  • Apply 15-30 minutes before going outdoors; re-apply every two hours.
  • Do not spare the sunscreen; 1 ounce (2 tablespoons) will cover unexposed surfaces on the average adult.

Sunscreen for teens

  • Acne-prone teens should use a gel or alcohol based product.
  • Sunscreens should not be used to increase sun exposure time.
  • Chronic tanning eventually leads to skin cancer, wrinkling, leathery skin and photo aging
  • Avoid tanning booths. Sun-bed use is a risk factor in the formation of melanoma.
  • Topical creams for artificial tan do not protect from the sun's rays unless they contain sunscreen.

Sunscreen for adults and the elderly

  • Sunscreen practices applied in youth and middle age should continue in elderly years.
  • Persons with dry skin should select creams or moisturizers with an SPF of 15 or higher.
  • Natural processes in aging skin include a decline in the skin's ability to repair damage produced by sun exposure due to a less effective immune system in the skin.
  • Cumulative photo damage results in thin, damaged skin that will worsen as more sun damage continues--sunscreen those rays!
  • The skin is less effective at sweating and cooling; elderly persons should wear regular lightweight, tightly woven clothing covering exposed surfaces, and should plan activities when the sun is not directly overhead and the air is cooler.
  • Most elderly people get enough vitamin D from exposure to UVRs; concerned individuals should consider vitamin D supplements.

Other sun protection measures

  • Wrap-around sunglasses block ninety-nine percent of UVA and UVB rays. Purchase contact lenses that offer UVR protection.
  • Select hats with a 3-4" brim or front and back flaps.
  • Tightly woven clothing that covers all exposed skin acts almost as a total shield from UVRs.
  • Typical summer fabrics have an SPF of 6.5; less if wet.
  • Watch the clock. Avoid UVR between 10 a.m. and 4 p.m.
  • Seek shade; thick tree = SPF 15, canopy of trees = SPF 30.

Health information

Learn about the sunscreen products available through our clinic.

More information

Additional information is available from the American Academy of DermatologyExternal Link Icon.