Sun Damage

The sun greets us when we awaken in the morning and calls us to rest as it sets. The timing of our daily activities, such as waking, sleeping and eating, are modulated by our circadian rhythms, and those are based on the sun. We need the sun for survival and sustenance.

The sun gives us health bonuses. Sunshine prevents the debilitating disease rickets because it works with the body to produce vitamin D, a necessary vitamin for health. In moderate doses, sunshine can heal immune system skin disorders, such as psoriasis and seborrhea. Your eyes need about 15 to 20 minutes of indirect sunshine a day for your hormones to function properly.

At the same time, the sun can destroy our health. Exposure to the sun causes the formation of free radicals on our skin. Free radicals are incomplete molecules that savage the electrons they need from other molecules, thus damaging the other molecules. They damage collagen and elastin, among others. Free radical damage leads to skin damage, aging, wrinkles, and skin cancer.

We need enough sun to be healthy, yet too much sun can make us look older before out time and can even kill us.

The sun radiates three kinds of light:
UVA is the most plentiful type of solar radiation and causes skin damage and skin cancer. UVA can penetrate glass, so you can even get too much sun from sitting in your car or near a sunny window. UVA doesn't feel hot and doesn't burn your skin.
UVB is stronger than UVA and can cause instant skin damage by causing a blistering sunburn.
UVC is filtered out by the earth's ozone layer. However, as the earth's ozone layer continues to be depleted, more UVC radiation reaches the earth. It's also damaging to the skin.

All solar radiation produces free radicals and all solar radiation can give you sunburn, skin damage, and potentially skin cancer.