Protection from the sun's UVA and UVB rays is widely recognized as one of the best ways to keep skin looking young and healthy. You may not know it, but skin care experts attribute unprotected sun exposure as the cause of more than 85% of skin aging. From wrinkles to saggy skin and age spots, keeping your skin protected against UVA and UVB rays is the simplest and least costly anti aging treatment available today. What's more important than keeping skin looking young, however, is that protecting skin from the sun can also help to protect you against skin cancer, which is on the rise worldwide.

Important Characteristics of a Sunscreen

In order to protect skin well, a sunscreen must posses certain characteristics:
1. It must protect against both UVA and UVB rays. UVB rays are shorter rays that cause tanning and sunburns. They are most prevalent during the summer and between the hours of 10am and 4pm. During these times, protection from UVB rays is important if you want to avoid a sunburn. UVA rays, are prevalent year round, during the winter and even on cloudy days. They can penetrate through windows and travel deeper through the skin where they can cause more longer damage. These permanent effects include skin damage such as wrinkles, premature skin aging, saggy skin and pigmentation issues. Both types of rays have been linked to the development of skin cancer.
2. It must be photostable. Photostability refers to the ability of a sunscreen to maintain its integrity when exposed to sunlight. Many sunscreen agents (avobenzone or Parsol 1789 is particularly problematic if it is not stabilized with another chemical) will degrade upon exposure to the sun rendering them useless. Read labels carefully to ensure that you're getting a product that delivers over time.
3. It should feel good on the skin. Though this seems like a very silly characteristic, it couldn't be further from the truth. Sunscreens only work if you use them so if you are forced to apply a greasy, unappealing substance to your skin, chances are that you won't use it. So what's the point of purchasing it in the first place?

Sun Filters that Work

There are two types of sun filters - those that are chemical and those that are physical.

Physical filters sit on top of the skin reflecting light away from the surface. The most well known physical filters include titanium dioxide and zinc oxide. Both offer varying levels of protection against UV rays and are photostable. Titanium dioxide blocks UVB rays only, while zinc oxide blocks across a broader spectrum of both UVA and UVB rays. These filters are often combined with one another or other sun filters to afford effective protection. One of the downsides of these sun filters is that they can leave a whitish cast to the skin. Newer micronized or nano particles tend to be less problematic.

There are a wide range of chemical filters on the market. All differ in their ability to block UVA and UVB rays and in their ability to retain their stability upon exposure to sunlight. It's beyond the focus of this article to examine each and every physical sun filter, but here are some of the newer, more effective and widely used ones:
Mexoryl SX (ecamsule) - a photostable blocker of both UVA and UVB rays.
Mexoryl XL - a photostable blocker of UVB and longer wavelenght UVA rays. The two Mexoryl molecules deliver greater protection when combined together than either agent used alone.
Tinosorb M - UVA and UVB ray protection; photostable
Tinosorb S - like Tinosorb M, Tinosorb S offers broad UVA and UVB protection and is photostable
Avobenzone (Parsol 1789) - an excellent blocker of both UVA and UVB rays, but avobenzone must be stabilized. Octocrylene is often used to stabilize it.

Choose a sunscreen with sun filters that deliver, that is photostable and that feels good on the skin. Apply about 20 minutes before sun exposure and reapply every 2 hours especially if you sweat or are exposed to water. Most of all, remember to use it daily, year round.