Skin cancer is caused by exposure to ultraviolet light, UVA or UVB, from sunlight. Avoiding direct exposure to sunlight is the most effective way of preventing skin cancer, but of course, there are times when that just isn’t practical.
Sunscreen is the most important product available to help block ultraviolet light for those times when we have to be in the sun. Three important factors to consider with sunscreen use are:
- the spectrum of UV radiation absorbed.
- the amount of sunscreen applied.
- the frequency of application.
The sun gives off three types of ultraviolet (UV) radiation based on the wavelength. All UV rays cause skin cancer!
- goes deeper into the skin (dermis).
- causes premature aging and wrinkles.
- also causes tanning.
- affects the skin’s surface (epidermis).
- contributes most to burning of skin.
- also damages your eyes.
- very dangerous but mostly filtered out by the ozone layer.
How to pick the proper sunscreen
The SPF (Sun Protection Factor) measures the amount of UVB absorption (there is no method of reporting the UVA absorption). The only way to determine if a sunscreen protects against UVA and UVB radiation is to look at the label. Look for:
- the words broad-spectrum (this means it blocks both UVA and UVB).
- an SPF of at least 30 (SPF means Sun Protection Factor and indicates the strength of the sunscreen you are purchasing; the higher the number the better).
Applying Sunscreen Properly
The most common mistake people make when using sunscreen is not using enough and not applying frequently:
- Sunscreen should form a film on the skin when initially applied.
- It takes at least 20 minutes for sunscreen to be absorbed by the skin; it should be applied at least 20 minutes before going out in the sun.
- Reapply every two hours.
- Reapply after swimming or perspiring.
- Alternate application of sunscreen with application of bug sprays.
- Apply sunscreen after moisturizers and before makeup.
Sunscreen should be applied daily, all year round. The sun’s rays reflect off surfaces such as snow, sand and even concrete, so whether you are at the beach, skiing in the mountains or walking down the street, you need to protect you skin from exposure to UV radiation.