Fun in the Sun...Don't Forget the Sunscreen

Using sunscreen can help prevent sunburn, skin cancer, visual pathologies, and premature aging of the skin. Sunscreen protects the skin (the body’s largest organ) against the harmful effects of ultraviolet (UV) radiation. Chemical sunscreens absorb UV rays and are regulated by the U.S. Food and Drug Administration (FDA) as over-the-counter (OTC) drugs. No matter what type of color or skin, all persons should use sunscreen, especially if you will be exposed to the sun for 10 minutes or longer, especially between the hours of 10:00 a.m. and 4:00 p.m. when the rays of the sun are the strongest. UV rays can damage the skin during any time of year, so sunscreen should be used year round. Did you know that more than 60% of the sun’s UV rays penetrate the clouds and can reflect off of surfaces such as water, sand, snow and concrete? Skin exposure to the sun helps the body produce vitamin D, but it is by far much healthier to use sunscreen and add vitamin D by ingesting multivitamins and drinking vitamin D-fortified milk.


What Kind of Sunscreen Should You Buy?
Sunscreen is available in a number of forms including gels, lotions, ointments, creams, wax sticks and sprays. There are formulas that are sweat and water resistant and products made for sensitive skin. The American Academy of Dermatology (AAD) recommends the use of sunscreen that blocks both UVA and UVB rays. Read the product labels! It is recommended to use products containing the physical blocking agents titanium dioxide, zinc oxide, helioplex or mexoryl, which offer the most broad spectrum coverage to block both UVA and UVB rays.

What is SPF?
Sunscreens are classified by the strength of their SPF. This rates the product’s ability to protect from UVB rays. The higher a sunscreen’s SPF, the more UVB rays are deflected. According to the AAD, examples of a sunscreen’s ability to deflect UVB rays include:

SPF UVB Rays Deflected
30 97%
15 93%
2 50%

SPF rating is calculated by comparing the length of time it takes for unprotected skin to turn red versus protected skin. For instance, a light-skinned person may burn after 10 minutes of unprotected sun exposure. Protected by sunscreen with an SPF of two, the same person would burn in 20 minutes. So, a sunscreen will offer protection. A sunscreen rated SPF 15 would provide the same fair-skinned person with protection for 15 times longer, or 150 minutes. Those persons with fair skin should use products with higher SPF ratings. Sunscreens that are water-resistant or waterproof are more effective because they are not as easily removed by sweating or swimming. Children over the age of 6 months can safely use sunscreen. However, they should only use sunscreen that is especially made for children. Parents should consult with their child’s pediatrician before applying any product to their child’s skin. People who are prone to acne may benefit from a water-based, non-comedogenic formula, because this type of sunscreen does not clog the pores. A cream-based sunscreen is usually less irritating than sunscreen in a gel or lotion form. Creams are a good choice for people with sensitive or dry skin. People who have allergic reactions may benefit from using a chemical-free physical sunscreen that contains zinc oxide or titanium dioxide.

Application of Sunscreen
Sunscreen should be applied to dry skin about 20 to 30 minutes before heading outdoors. Enough sunscreen should be used to completely cover all areas of exposed skin, including the nose, ears, neck, hands and feet. Sunscreen should also be applied to any areas of the scalp that are exposed. It is safe to apply makeup over sunscreen. Sunscreen-containing cosmetics are also available. Follow the manufacturer’s directions regarding reapplication. In general, sunscreen should be reapplied at least every two hours and reapplied immediately after getting out of water. Some sunscreens also contain insect repellants. These products are less effective, so use separate sunscreen and insect repellant products. Sunscreen products have a shelf life. Check for an expiration date on the packaging.

Source: Medscape June 2009