Do you know the difference between a sunscreen and a sunblock?
Chemical sunscreens often are colorless and maintain a thin visible film on the skin. These sunscreens usually contain UVB absorbing chemicals and more recently contain UVA absorbers as well. A chemical sunscreen absorbs the sun's rays like a sponge and then creates a chemical reaction on the skin to break them down. This kind of chemical sunscreen takes at least 15 mins to take effect.
A physical sunscreen often referred to as a sunblock containing the usual Zinc and Titanium minerals reflect all UV rays and immediately take effect upon application. These natural minerals are what gives mineral makeup its SPF factor.
I know there has been some controversy regarding sun protection products but to date there has not been any scientific studies to prove that sunscreens are carcinogenic. However, it has been proven and documented that UV rays are dangerous...and in addition, many of us have either seen or experienced the proof that UV rays are in deed carcinogenic.
What does SPF mean and how is it rated?
SPF means sun protection factor...if it takes you on an average approximately 10 mins out in the sun to burn and you are applying an SPF 15 then you have up to 150 minutes of sun exposure to before you would begin to burn. This is not an exact science because when these numbers were being tested the amount of SPF that was applied has been proven to be much more than what people are applying to themselves when going out. In addition, water and sweat proof products are misleading people into thinking they are safe all day. My rule of thumb is over apply, apply often, and apply EVERYWHERE.
SPF is not to be considered protection, but just how long it will take for the skin to get reddened while being exposed as opposed to not wearing a SPF during exposure.
SPF15 sunscreen is screening against 93% UVB, SPF 30 97% and SPF 50 98%. So essentially going higher to a 70 in my opinion is not going to give you that much more UVB protection but gives a lot more false hope and therefore greater chance of misuse. Since you need "protection" from UVA rays as well, look for a product that is a broad or multi spectrum product to include UVA protection as well. However there are no certainties to how much protection is provided for in regards to UVA rays.
What are UV Rays?
UVA are longer range UV rays and account for up to 95% of the rays that we are exposed to on a daily basis. Although these are less intense than UVB rays they are more prevalent in that we are being exposed to them in equal intensity throughout the day and throughout the year, through glass and through clouds. UVA rays have been referred to as the aging rays because they reach deeper into our skin where the collagen and elastin fibers are produced, damaging and breaking them down as well as slowing their production causing sun damage and deep wrinkles. These rays are also responsible for damaging skin cells in the lower layers of the skin where they are produced which can lead to the formation of Basal and Squamous Cell Carcinomas in the skin. UVA rays are the primary rays chosen by tanning salons because of the damage to the DNA of the skin cell that creates the Melanocyte (pigment producing cell which acts as the bodies defense to protecting the skin cells) when the UVA rays hit the skin cells...the Melanocytes excrete Melanin (pigment produced by the cell) which travels to the surface of the skin to act as a barrier of further penetration and damage to the DNA of the cells. Repeated exposure to these DNA damaging rays can also lead to damage to the Melanocytes causing Melanoma.
UVB are a shorter range UV rays and are called the burning rays because they are more intense. These rays vary by season, location, and time of day. In the US between 10 AM and 4 PM from April to October are most significant in regards to UVB rays. However, UVB rays can burn and damage your skin year-round, especially at high altitudes and on reflective surfaces such as sand, snow or ice, which bounce back up to 80 percent of the rays so that they hit the skin twice. Skiers beware, ultraviolet radiation increases 4 percent for every 1,000-foot increase in altitude.These rays inflict damage on the upper layers of the skin playing a key role in skin cancer and contributing to sun damage of the skin.
Other UV protection...
Windows - You are not being protected by the sun's rays in your car, home, or business unless your windows have been tinted with a UV protection tint that blocks 99.9% of the sun's UV rays and allows 80% of the light in.
Clothing - UPF clothing that has a rating of 30 means that 1/30th of the sun's rays are reaching the skin.
How much sunscreen should you use and how often should you apply it?
Sunscreens should be used daily as they decrease the likely hood of damage and may even contain other ingredients to further repair damaged skin when used on a regular basis. Even on a cloudy day 80 percent of the sun's ultraviolet rays pass through the clouds.
Pay particular attention to your face, ears, hands and arms. Apply sunscreen liberally using one ounce to completely cover your body. Lips get sunburned too, so apply a lip balm that contains sunscreen with SPF 15 or higher. Remember, waterproof sunscreen begins losing effectiveness after 80 minutes in the water, so reapply sunscreen before this time, especially if you have towel-dried for maximum protection.
Is there a difference between waterproof and water resistant?
The FDA considers a product "water-resistant" if it maintains its SPF level after 40 minutes of water exposure. A product is considered "waterproof" if it maintains its SPF level following 80 minutes of exposure to water. If you participate in outdoor recreational activities including swimming, you may want to choose a waterproof sunscreen.
