Groovee Uuuuuveee

We have all heard about the UV index but I am willing to bet that very few of us actually understand what in the world it is and what it tells us…if you believe that all the hullabaloo about sun damage and sunscreen is BS or overblown, the UV index (science) can definitely set you straight. It sort of cuts to the heart of “it” all. And the stats (Melanoma is the third most common cancer among women aged 20-39 years and the second most common cancer in men aged 20-39 years) prove it.

There are three types of sun rays that have been discovered: the A, B, and C rays. We are concerned with the A and B rays because the C rays are too short to actually hit the surface of the earth. When I was growing up (#agingmyself), we only talked about the B rays, i.e. “avoid sunburn!”, “don’t go to the beach between 10 and 2”, “if it’s cloudy, you don’t need sunscreen”. All that is true in relation to the sun’s B rays. Think “B” for burning. B rays are shorter than A rays and don’t penetrate through windows for example. They are also not as strong during the morning and evening hours. B rays are known to cause mutation of the skin’s cells which can lead to skin cancer.  The A rays however, are longer, can penetrate windows and clothing, are as strong in the morning as they are in the evening, can penetrate clouds, and can reach deeper into the different skin’s layers, mutate cells, and have been linked to skin cancer, as well as aging of the skin. Think A for aging. Neither A rays or B rays are good.

The UV index in layman’s terms, melds the risk of the two rays together at any one time of day in the location where you are and tells you the risk from the sun’s rays. The ranges are as follows:

Important things to note that effect our day to day lives and those of the ones we love: even at a UV index level of 3, sunscreen is recommended. Lotion or cream based sunscreen absorbs throughout the day, and hence that’s why you have to reapply it, or use sunscreen that does not absorb (see link to some I like here). Other precautions, even at a UV index level of 3: wear sun protective clothing, a wide-brimmed hat, and UV-blocking sunglasses when outdoors.

Yea, yea, you say, but when is the UV index at a 3 for example? Well, there are several apps for that! Personally I like the Dark Sky app because it will tell you the UV index level expected for the day over time and you can gauge what you are up against for the next several hours. For example, here are screenshots for two different days for my area of San Francisco. Note how quickly the morning goes from nada to 9 (World Health Organization says ”very high risk of harm from unprotected sun exposure”):

Other weather apps also show you the UV index, but not necessarily over time through out the day.

The bottom line: you gotta protect yourself and the ones you love and if you are getting resistance, the UV index provides scientific evidence and a protocol to follow!