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Understanding Sunscreen

Without question, sunscreen is the most important aspect of any skincare regimen. It is imperative to prevent skin cancer. Unfortunately , misleading and often incorrect consumer directed information has led many to believe that these crucial products are actually harmful. This article is aimed at dispelling some of these myths regarding these invaluable products and by understanding how sun protection works to safeguard the skin, you will be able to identify the most effective sunscreens on the market.

It is critical to realize that one does not have to be outdoors to be exposed. Human beings are constantly in contact with UV radiation, as it is emitted from multiple sources including the sun, tanning beds, black lights, germicidal lamps, halogen lights and fluorescent and incandescent lights. The almost unavoidable exposure to UV radiation makes daily sunscreen application essential for healthy skin. UV rays have been officially categorized as a known carcinogen.

UV rays are divided into three types: UVA, UVB, UVC. UVC radiation is almost completely absorbed by the atmospheric ozone. Exposure is minimal.
UVB rays are thought to be responsible for the majority of the sun’s negative effects on the skin. Although the inflammation and erythema produced by a sunburn is the most obvious change, it is what is happening within the skin that is the most worrisome. UVB radiation is responsible for a cascade of events inside the epidermis cells, including increasing levels of damaging free radicals and reactive oxygen species. In addition, UVB causes a reduction of the skin’s natural antioxidant levels, making it even more vulnerable to DNA damage and mutation. This damage is the number one cause of skin cancers. UVB rays can be remembered as the rays responsible for burning.
UVA rays makes up the majority of the rays that reach the Earth’s surface. UVA rays are believed to be the primary cause of premature visible aging. The deeper , dermal penetration of UVA leads to the breakdown of structural components such as collagen and elastin. UVA radiation is able to penetrate glass and most clothing, and its strength remains constant throughout the day, which makes daily sunscreen use imperative, even if one remains indoors. UVA rays also increase free radical damage and decreases the body’s natural defense mechanisms. Although UVA is thought to play a less significant role in carcinogenesis compared to UVB, it is still responsible for approximately 20 % of the sun’s cancer – causing effects.

UV Protection

Sunscreen agents are classified as physical or chemical. A physical sunscreen is a product that sits on the surface and reflects or scatters UV radiation before it induces cellular damage. A chemical sunscreen is a product that penetrates the corneocytes and absorbs UV rays before they effect the skin. A blend of the above is needed for ideal protection.

The term “SPF” is the abbreviation for a product’s Sun Protection Factor. It only indicates a products’s ability to screen the sun’s burning rays, or UVBs. It is a misunderstanding that a product’s effectiveness is solely determined by the SPF number. It is important to explain that the level of protection is not proportionate with the SPF rating. An SPF of 15 provides protection from 93 percent of UVB rays, SPF 30 protects from 97 percent of UVB rays and an SPF of 60 protects from 98 percent of UVB radiation. Many dermatologists believe that an SPF higher than 30 is of little value.

In addition , people often incorrectly believe that re-application is not warranted when using a high SPF product. In reality, nearly all sunscreen products break down and must be re-applied every two hours.

The term “ broad-spectrum” indicates a product’s ability to protect against both UVA and UVB radiation. At this time, the U.S. has not implemented a rating system for UVA protection. The only way to ensure that a sunscreen absorbs UVA rays is to read the ingredient label on the back of the bottle.
Water and sweatproof claims are false and irresponsible , as there are no such products. Products can be sweat- resistant, meaning that they are able to maintain their protective effects in water for a certain amount of time. All sunscreens should be applied after swimming, sweating, toweling off or vigorous outdoor activity.
Finally , sunscreens formulated with added antioxidant products provide superior protection against sun- induced free radical damage.

Further information on sunscreen ingredients are available at the OUTER IMAGE SPA.


Shelley Waldman