How to Prevent Sunburn

    Published: 06-16-2009
    Views: 12,354
    Dermatologist Amy Ross explains how to prevent sunburn.

    Amy Ross: My name is Dr Amy Ross. I am a Board Certified Dermatologist and this segment is on how to prevent sunburn. People often think that on a cloudy day they cannot get sunburn and this is absolutely not true. Even on the cloudy day, over 50% of the UV rays produced by the sun reach the surface of the earth. So it is possible to get a sunburn even on a cloudy day. Obviously, on days like today when the sun is bright and in increased intensity, there is an increased risk of getting sunburn more quickly, however, there is not any particular weather condition that will protect you from the sunlight. You should keep that in mind when going outdoors at any time because you should always wear sun protection. Suntan lotion is probably a misnomer because we should really refer to these agents as sunscreen because our goal is not to tan but it's actually prevent ourself from getting sun exposure. Sunscreens are chemicals that work in two different fashion. They either absorb the UV rays that are produced by the sun or they reflect the UV rays produced by the sun. Lots of the sunscreens on the market today are what we consider broad-spectrum and absolutely it is essential to buy a broad-spectrum sunscreen. These sunscreens will protect you from the shorter wavelength UVB rays as well as the longer wavelength UVA rays. So UVB rays are shorter wavelength rays and traditionally thought of as the sun rays responsible for Skin Cancer. However, we now know that UVB and UVA rays contribute to Carcinogenesis. It is important to know that UVB rays are the rays that are responsible for a sunburn so even if you are not getting burned, you can still be receiving a significant dose of UVA rays, which can also lead to Skin Cancer. When looking for a sunscreen, in addition to finding something that's broad spectrum, you need to pay attention to the SPF number and the SPF number stands for Sun Protection Factor and this is essentially ratio of the skin reaction developed on unprotected skin compared to protected skin. So I can explain that a little more. In theory if you burn after 20 minutes in sun exposure without any protection on your skin at all and then applied a SPF 15 product, that in theory will protect you 15 times longer than you would be without the sunscreen on. So that would be equivalent to about five hours of sun protection. An SPF of 15 blocks 93% of all the UVB rays that will be absorbed by your skin and SPF of 30 blocks 97%. and an SPF of 50 block 99% of all the UVB rays. So SPF is an important number to look for, to find out if the sunscreen will protect you from UVB rays. However, you often need to make sure that again the product is advertised as board-spectrum. A common ingredient that will protect you from the UVA rays include Zinc Oxide, Titanium Dioxide. These ingredients are the important chemicals that will protect you from the UVA rays. In order to properly apply suntan lotion you should start 30 minutes before you leave and head outdoors. Applying at least one ounce which is equivalent to about two tablespoons to your entire body 30 minutes before heading outside is the best way to start with sun protection. However, it is very important to know that you have to reapply sunscreen every two hours. Most people do one of two things, either they only apply a small amount of sunscreen, not the full one ounce necessary in order to achieve that SPF that is advertised or they don't reapply and reapplying every two hours is very important to protect yourself from the sun. You should reapply more frequently if you are in the pool, if you towel off or if you excessively sweat. So we always think about sunscreen as the major way to protect ourselves from the sun and this is very very important. However, there are other things that we can do in order to protect us from the sun. The best thing to do would be to avoid the sun between the hours of ten and four because that is when the sun rays are at the peak intensity. Another way to protect yourself form the sun is to wear sun protective clothing and nowadays there are many articles of clothing that are labeled with something called UPF and this stands for Ultraviolet Protection Factor. This is a equivalent to an SPF in a sunscreen but the UPF is the protection factor in clothing. These are very commonly available and are a good source of protection.

    The final thing you can do to protect yourself from the sun, if you have to be out in the sun is to wear a hat and a baseball hat is very modestly helpful. In order to actually have a hat that does have sun benefit, the brim on the hat should be about 4 inches in diameter, so we are talking about a wide brimmed hat and that will help contribute to sun protection.