The Importance of Sunscreen
Just because it’s a cloudy day does not mean you are safe from the sun’s rays. The sun’s ultraviolet light rays can cause pre-mature aging, skin discoloration, and skin cancer. Most skin damage occurs before the age of 18. When choosing your sun screen, choose a minimum of SPF 15 (no higher than 50) and make sure titanium dioxide, zinc oxide, avobenzone, or meroxyl is in the ingredients list to ensure you are getting protection against UVB and UVA. Also wear a SPF 15 lip balm. Reapply sunscreen every 1.5 to 2 hours.
Sunburn is the most immediate and most obvious result of overexposure to the sun and is essentially the inflammation of the skin. Mottled pigmentation (freckles, age spots), pre-mature wrinkles, lower immunity against infection, solar elastosis (breakdown of elastic tissue), and of course, skin cancer: these are results that many people are not aware of brought on by unprotected exposure to the sun. Your skin is the largest organ of your body and just like the rest of your health you should be taking care of it. But what is it about the sun that damages our skin?
An Invisible Culprit: Ultra Violet Radiation
Despite the sun’s physical and psychological benefits to our bodies, sunlight accounts for 90% of the symptoms of premature skin aging. The sun gives off what’s known as ultraviolet (UV) radiation which falls into three categories base on wavelength:
- UVC – 100 to 290 nm (1 nanometer = 1 billionth of an inch)
- UVB – 290 to 320 nm
- UVA – 320 to 400 nm
While UVC is absorbed into our ozone layer, resulting in no effect on us (but would otherwise be deadly), UVB and UVA still pass through the ozone layer and can harm our bodies.
UVB: UVB affects the top layer of our skin, the epidermis, causing sunburns. Although 90% of UVB is absorbed by the ozone layer, that 10% is enough to damage our skin. UVB penetrates clouds does not penetrate glass and is more intense during the summer between the hours of 10:00 AM and 2 PM when the sun is brightest.
UVA: UVA affects the deeper layer of our skin, the dermis, and causes skin cancer (the most prevalent of cancers in the US ) and aging. It is not only unaffected by the ozone layer, but it also goes through glass and is more constant than UVB.  Over time, ultraviolet light breaks down the elasticity of our skin, causing our skin to sag. The skin begins to bruise and tear easily. It creates free radicals—unstable organic molecules responsible for aging and possibly some diseases—damaging the repair mechanisms of our skin. 
What is SPF?
SPF stands for Sun Protection Factor is a measure of protection against UVB only. The higher the SPF, the more protection is provided. However, the FDA plans to limit the maximum SPF rating of sunscreen labels to “50 +” in 2012 as, “there is not sufficient data to show that products with SPF values higher than 50 provide greater protection for users than products with SPF values of 50.”  Furthermore, while it is logical to think an SPF 30 product would be twice as effective as an SPF 15, it is not true. “An SPF 15 product blocks about 94% of UVB rays, an SPF 30 product blocks 97% of UVB rays, and an SPF 45 product blocks about 98% of rays.”  The FDA recommends that you regularly apply sunscreen of SPF 15 or higher to protected uncovered skin. 
What is the PA rating system?
The PA system is used throughout Asia and stands for Protection Grade of UVA. It is based on the Persistent Pigment Darkening (PPD) reaction reading at 2-4 hours of sun exposure—a method of measuring UVA protection, similar to the SPF method of measuring UVB light protection.  PA ratings will usually look like this:
PA (some UVA protection, PPD of 0-2)
PA+ (strong UVA protection, PPD of 2-4)
PA++ (very strong UVA protection, PPD of 4-8)
PA+++ (strongest UVA protection, PPD > 8 )
Most sunscreens made in the US will not have this rating. Instead they specify “broad spectrum” protection or specify protection against UVA/UVB.
How to Choose the Best Sunscreen
To be an effective sunscreen, a product MUST have a few certain ingredients. When choosing your sunscreen, to be sure to check the label for at least one of the following:
- Titanium Dioxide
- Zinc Oxide
- Avobenzone (Parsol 1789)
Or check the front label for PA++ or higher. This will give you the broad spectrum of protection you need. Also choose a minimum SPF of 15 but no higher than 50. If you have fair skin, choose a higher SPF.
If you are planning on hopping in the pool or ocean, you may want to consider a water-resistant sunscreen. The FDA will be permitting only two labels of water-resistant claims on products: 40 minutes or 80 minutes (in reference to protection after immersion in water). Manufacturers will also no longer be able to claim that their sunscreen is waterproof, sweatproof, provide instant protection, or protect more than two hours without reapplication unless they submit data and get approval from the FDA. 
Also choose a lip balm with a minimum SPF of 15. Lips are just as important to protect from the sun.
When and How to Use Sunscreen
Use sunscreen whenever you go outside, even on a cloudy day, and apply it 30 minutes before exposure to give it time to absorb into the skin. Apply a liberal amount to your entire face and body including the:
- Back of neck
- Tops of feet
- Areas of head exposed by balding or thinning hair
An average-size adult needs at least one ounce of sunscreen (a shot glass’s worth) to cover the body from head to toe. Sunscreens typically need to be applied every 1.5 to 2 hours. Reapply your SPF lip balm every hour. If your sunscreen is expired, throw it out. The chemicals in the product will eventually break down and result in being less effective. Be sure to also use other methods of protection such as sunglasses that are labeled with UVA/UVB rating of 100%. The darkness of the lens does not indicate its ability to shield your eyes form UV rays. 
Note: When using an insect repellent, a higher SPF should be used. Insect repellents reduce the effective SPF by one-third. Apply your insect repellant first. 
If you want to avoid wrinkles, age spots, or other pre-mature aging symptoms and decrease your risk of developing skin cancer, wear sunscreen every time you go out during the day. Be sure to read the ingredient labels for key ingredients like titanium dioxide or zinc oxide and choose an SPF that is 15 to 50. While no sunscreen is 100% effective at blocking the sun’s UV rays, these simple practices will make or keep your skin looking youthful as you get older.
|Sun protection solutions by Atomy|
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