With the summer upon us, it’s time to get into the sunshine spirit of things. We tend to love our time in the sun, but we may not always protect ourselves. Some of us want a fresh glow on our skin; others just want to get out of the house after the long winter. However, we have to be aware of how the sun affects us. Besides the positive benefit of the vitamin D that our bodies produce because of sun exposure, the ultra violet (UV) rays that aren’t scattered by the earth’s atmosphere have negative effects on our skin.

We classify three categories of UV light that hit our earth’s atmosphere: UV A, UVB and UVC. UVC is the least of our concern, as it is scattered by the earth’s atmosphere. The important thing to know about the other two categories of UV light is the effect each has on our skin. The easiest way to remember the difference between the two categories of UV light is to recall that UVA causes wrinkles, and UVB causes cancer. This, of course, is a generalization and the details are more complicated, but it’s a good rule of thumb.

So how do we protect ourselves from UV light? Well, there is an enormous amount of information about sunburn protection on the Internet, but from a scientific point of view, the most important questions may be: Are the protection methods effective against skin damage? Will the sun protection prevent our bodies from producing enough vitamin D? Are the protection methods more dangerous to our skin than the sun itself?

I’ll leave out the vitamin D deficiency question and let you discuss your nutrition with a specialist. With respect to the other two questions, we must consider the most commonly used methods of sun protection ~ the first being stay out of UV light! That means staying covered when going out in the sun, and it means staying out of tanning beds. The main danger of staying covered is, of course, dehydration in the hot sun. So wear clothing that keeps you cool and keep hydrated and drink plenty of water.

The other most common protection method is sunscreen. Sunscreen is generally rated with an FDA-approved Sun Protection Factor (SPF). The SPF number is a ratio of two measures. That is, you divide the amount of UV exposure required to cause a superficial reddening of the skin with the sunscreen, by the amount of UV exposure required to cause a superficial reddening of the skin without the sunscreen. The result of this division is the SPF of the sunscreen. Manufacturers determine this measure with standard accepted scales from scientific research.

Sunscreen is generally made from with two types of particles to block or absorb the UV light, ~ zinc or titanium. There are a number of studies which say our bodies do not suffer ill effects from the zinc and titanium exposure, so the products are likely safe, according to the FDA and a number of researchers. The important thing to keep in mind here is that SPF doesn’t have anything to do with how long you can stay in the sun.

The bottom line is follow the advice on the label of your sunscreen with regard to application, and according to most of the sources I checked, SPF 15 is the minimum SPF you should wear, with SPF 30 providing slightly more protection.

By R.J. Linton