From a young age, we are taught to protect our skin every time we expose it to the sun's rays. Unprotected skin can lead to premature aging and in the worst case scenario, it can lead to fatal cases of skin cancer. Since many people would rather not avoid the sun or the outdoors altogether, people slather on sunscreen to stay protected. But research is showing that some sunscreens may not be safe for use. 

What You Should Know

There are two basic types of sunblocks:

• Mineral sunblocks
• Chemical sunblocks

Mineral sunblocks are the good old standbys, such as Zinc Oxide (diaper cream) and titanium dioxide. These substances provide a barrier that the UVA and UVB rays cannot penetrate. This barrier provides a physical protection for the skin.

Chemical sunscreens such as oxybenzone, avobenzone, or octisalate are applied to the skin and offer protection as the products absorb and dissipate the heat and rays from the sun and prevents the skin from becoming burned. There are some questions regarding the absorption of oxybenzone into the blood stream and it has been recommended that widespread application of oxybenzone products over large areas of skin should be avoided.

There is also some concern of oxybenzone being applied to the skin of young children, as they have a greater skin surface area versus weight ratio than adults. Thus, the absorption concentration of the oxybenzone would be higher in the young child. This is of concern as the elimination process of young children and babies is not adequately developed to rid the body of any chemicals that are absorbed through the skin into the blood stream.

What to Look For 

The sunscreen should provide protection from UVA and UVB rays. The sunscreen should be labeled "broad spectrum." This means that it provides UVA and UVB protection.

In addition to UVA and UVB, the "sun protection factor" (SPF) and the persistent pigment darkening (PPD) factor should be considered. SPF has been the poster child for most sunscreens and consumers have become savvy with the SPF figures on most sunblocks. The SPF is a number associated with how well it protects against the burning of UVB rays. PPD is a measure of how well a sunscreen protects against photoaging.

In each case, the higher the number the better the protection. For everyday use, most dermatologists recommend that a minimum SPF of 15 be used. If consumers are gardening or outside a higher SPF, such as 30, should be applied. If a day at the beach is in order, then bumping up the protection to a SPF 40 or even higher may be necessary for exposed skin. The PPD number should be around 8 or higher to prevent skin damage from UVA rays.

When applying sunscreen make sure that enough is used. Most people use a quarter-sized dollop, but the FDA recommends using around one ounce (think shot glass full) of sunscreen to protect exposed body parts. The sunscreen should be applied frequently, around every two hours, as water from swimming and perspiration will reduce its protectiveness.

Sun protection products are administered by the Food and Drug Administration and are regulated as an over-the-counter drug. In addition, the benefits of applying sunscreen is "an important tool in the fight against skin cancer," says the American Academy of Dermatology.