From Dr. Joseph Mercola:
Having concern about skin cancer is valid, as 
its incidence in the United States has tripled in recent years to 54,000 cases annually. This article takes the position that sunscreens don't block UVA, which makes them ineffective.
You must exercise caution. At the beginning of the season go out in the sun gradually, perhaps as little as 10 minutes a day. Progressively increase your time in the sun so that in a few weeks you will be able to have normal sun exposure with little risk of skin cancer.
Remember never to get burned, that is the key. Remember also never to use sunscreen, another key. You can creatively use your clothing to block the sun’s rays during your build-up time.
The bottom line is, please avoid getting sucked into the hype that sunlight is dangerous. It is only dangerous if you are clueless about fat nutrition, which most medical doctors are.
