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Cancer Types - Sunscreens

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Cancer Types - Sunscreens

Picture of two young girls giggling by the side of the pool

What are sunscreens?

Sunscreens protect the skin against sunburns. Sunscreens also play an important role in blocking the penetration of ultraviolet (UV) radiation, which damages the skin and can lead to skin cancer. However, no sunscreen blocks UV radiation 100 percent.

What is the difference between a sunscreen and a sunblock?

The terminology used on sunscreen labels can be confusing. The protection provided by a sunscreen is indicated by the sun protection factor (SPF) listed on the product label. A sunblock is considered to be any sunscreen with an SPF of 15 or more. In theory, sunscreens protect an individual during an incident of ultraviolet B (UVB) radiation exposure according to the following:

  • SPF 15 sunscreen may absorb more than 92 percent of UVB radiation.
  • SPF 30 sunscreen may absorb 97 percent of UVB radiation.

How to use sunscreens:

A sunscreen protects from sunburn and minimizes suntan by reflecting UV rays. Using sunscreens correctly is important in protecting the skin. Consider the following:

  • Use of a sunscreen with SPF of 20 to 30 offers substantial protection against sunburns, and usually prevents tanning.
  • Choose a broad spectrum sunscreen that filters out ultraviolet A (UVA) and ultraviolet B (UVB).
  • A sunscreen that provides an SPF under 4 offers the least protection. If you rarely burn and always tan, this level of skin protection may be sufficient to help prevent burning and uneven coloration.
  • Sunscreens with high SPF sunscreens protect from burning for longer periods of time than do sunscreens with lower SPFs.
  • Apply sunscreens to all exposed areas of skin, including those easily overlooked areas such as the rims of the ears, lips, back of the neck, and feet.
  • Sunscreens are recommended for everyone (over 6 months of age), regardless of skin or complexion type, because all skin types need protection from solar UV rays. Lighter skin types are at the greatest risk of developing skin cancer; but all people are at some risk. Research has shown that UVA rays may contribute to premature aging and skin cancer.
  • Apply sunscreen liberally. The recommended dose is one ounce per application. Reapply every two hours, after being in the water, or after exercising or sweating. Incidental time in the sun could add up to a sunburn. Do not forget the time spent walking your dog, window shopping, or jogging on your lunch hour.
  • Do not forget the sunscreen when performing outdoor chores.

Matching sunscreens with skin type:

Knowing your skin type can help you pick the right sunscreen for you. The US Food and Drug Administration (FDA) recommends the following:

Sun Exposure History Recommended Sun
Protection Factor (SPF)
Burns easily, rarely tans 20 to 30
Burns easily, tans very little 12 to 20
Burns moderately, tans gradually 8 to 12
Burns minimally, tans well 4 to 8
Rarely burns, tans well 2 to 4

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