With winter upon us, many people ask if sunscreen use is necessary in the winter.  The simple answer is yes.  Now we will consider the reason why sun screen should be used.  Although the sun may not seem as hot during the winter months, the sun still is emitting ultraviolet radiation which is a major cause of skin damage, skin wrinkles, and certain types of skin cancer and premature aging of the skin.  The sun emits three types of ultraviolet radiation, UVA, UVB and UVC.  UVC is blocked by the ozone layer and does not reach the earth’s surface.  UVB has long been associated with sun damage and is the major cause of sunburns. UVA has recently been found to cause more damage to the skin than UVB for it penetrates to a deeper level of the skin and damages that layer. Unlike UVB, UVA is more consistent, in that there is no daily or seasonal variation in the amount of UVA that reaches the earth’s surface.

  Now that we understand a little about the sun’s damaging effect, what can we do to prevent the damage?  Sun block, at least SPF 15.  SPF stands for sun protection factor.  It is a measurement developed in the laboratory which measures the amount of light needed to induce redness in sun block protected skin divided but the amount of light to induce redness in unprotected skin.  A simple way to think about this is, if your skin gets red after 10 minutes of exposure to the sun, with SPF 15, it would take 150 minutes to develop the same amount of redness.  It is important to remember that SPF does not protect against UVA.

So why is it important to use sun block in the winter?  Simply because we should use sun block every time we are exposing ourselves to the sun.  The UV radiation does not stop just because it is winter.  The snow causes the reflection of UV radiation which can increase our exposure on bright sunny winter days.  Skiers are more susceptible because the high altitude allows more harmful radiation to hit our skin. Since we do not feel the typical burn of sunburn like in the summer, we tend to stay out for longer periods of time increasing our exposure. Although it always enjoyable to be outdoors on a lovely winter day, as you are dressing to enjoy the day, remember the sun block, you will thank me later.