As discussed in our last blog there are natural substances like astaxanthin that can provide some internal protection from sun damage. These seem to work through their powerful anti-oxidant and anti- inflammatory properties but as yet there is not a substance that one can take internally that will actually absorb the harmful UV rays from the sun in the same way that a topical application of sun protection will.
So the real answer is: any time you’re outside. It’s important to remember that sun protection isn’t just for days at the beach. Sun damage can happen whenever you come in contact with harmful UV rays—that includes when you are out walking the dog or driving in your car, early or late in the day when the sun is low, or even on overcast days. Remember: when you are fully dressed, your hands and face are still exposed, so a little daily sun protection is a good idea.
The most dangerous time to be outdoors without proper sun protection is between 10 AM and 3 PM, when the sun is at its peak. It is safest to stay indoors during those hours, but if you go outside, be sure to wear protective clothing or use a high SPF sunscreen and reapply it frequently and liberally.
Sun Protection and SPF
SPF, or Sun Protection Factor, is a rating system that determines how long a sunscreen protects your skin from the sun’s UVB rays. The SPF number is a measure of how much longer you can stay in the sun without burning while using a sunscreen versus how long you can stay without burning while wearing NO sun protection.
Say that your skin normally begins to turn red after 10 minutes of unprotected sun exposure. If you use a product rated SPF 2, your skin would not begin to burn for twice that amount of time: 20 minutes. If you use a sun product rated SPF 25, you could stay in the sun for 250 minutes, a little over 4 hours (25 x 10 minutes) before your skin would start to turn red. Remember, though, that SPF numbers are not absolute. It all depends on how fast or how slowly YOU start to burn. If your unprotected skin burns in 5 minutes, an SPF 25 product might let you stay in the sun a little over 2 hours without burning (25 x 5 minutes = 125 minutes).
Here’s something else to keep in mind: The SPF measures only the level of protection from UVB rays, the ultraviolet rays that cause sunburn, and does not measure levels for the far more dangerous UVA rays, which penetrate the skin more deeply and can cause damage at the cellular level. When choosing a sunscreen, it’s important to look for one that offers broad-spectrum protection from both UVA and UVB rays.
Sun Protection and UV Rays
Rays of light from the sun are different lengths. Some of those lengths result in the different colors you see. UV rays are shorter than the shortest rays in the visible-light spectrum, which are the ones your eyes perceive as the color violet. (UV stands for “ultraviolet.”) There are 3 types of UV rays:
- UVC rays are the shortest, so short that they usually don’t make it through the Earth’s ozone layer to reach your skin. When it comes to sun protection, UVC rays are not a concern.
- UVB rays are a little longer, and can penetrate the skin, but not too deeply, reaching only the outer layers (epidermis). UVB rays are responsible for causing your skin to tan and/or burn. Longterm exposure to UVB rays can rapidly age your skin, making it look leathery and wrinkled.
- UVA rays are the longest UV rays, and can penetrate more deeply, into the dermis, the second layer of your skin. They can do serious damage at the cellular level, causing cellular changes that can lead to skin cancers. They are a primary cause for photo aging, wrinkles and skin discoloration.
“Critical wavelength” is the international rating system for UVA protection, defined as the point at which a sunscreen allows 10% of UVA rays to penetrate the skin. The FDA has determined sunscreens with a critical wavelength of over 370 nanometers provide excellent protection. (For information on what constitutes a nanometer, see “What are nanoparticles?” question below.) Aubrey’s Natural Sun SPF 30+ sunscreens have a critical wavelength of 375 nm.
How do Aubrey’s sun protection products work?
There are two main types of sunscreens. Chemical sunscreens work by absorbing UV rays before they have a chance to penetrate and damage the skin. (These types of sunscreens are more controversial because they are easily absorbed by the skin and can cause allergic reactions, irritation and other more serious concerns.) Physical barrier sunscreens form a protective layer on top of your skin that blocks and reflects the sun’s harmful rays.
Aubrey’s Natural Sun sunscreens are physical barrier sunscreens, formulated with micronized titanium dioxide and zinc oxide as the active ingredients. Titanium dioxide and zinc oxide are naturally occurring minerals, and are among the 17 ingredients approved for sun protection by the FDA. Since both are white in color, the larger the particles of these ingredients, the more of a whitish film they leave on your skin. “Micronized” simply means they are ground into a very thin powder made up of particles so small, they are measured in either microns or nanometers (nm). The smaller the particles, the less visible the ingredients.
What are nanoparticles? Should I be concerned?
A nanoparticle is a very tiny piece of a solid substance. “Nano” means “billion,” and a nanoparticle is defined as a particle smaller than one billionth of a meter (a nanometer, or nm). Nanoparticles of zinc oxide and titanium dioxide are often used in sun products to minimize the white film these ingredients can leave on the skin.
Some consumer groups have raised concerns about nanoparticles, fearing that something so small could penetrate the skin, get into deeper tissues, and have adverse health effects. This issue has been studied extensively over the past five years. The overwhelming number of current studies indicates that nanoparticulate titanium dioxide and zinc oxide do not get past the epidermis. The FDA has determined nanoparticles are safe when used in cosmetics and sunscreens.
That said, our testing has shown that the average particle of micronized titanium dioxide in Aubrey sunscreens has an average size of 202 nm, or twice the largest size considered a nanoparticle, while the average zinc oxide particle is more than 1,000 nm, or ten times the size of a nanoparticle.
Experience Aubrey, all natural since 1967. Safe, smart, natural sun protection you can count on available here at Willner Chemists Atlanta.