UV radiation does have some benefits, one of which is that it helps our skin manufacture Vitamin D. The benefits of Vitamin D are well documented. It is an important nutrient that helps the body maintain normal levels of calcium and phosphorous in the blood. Vitamin D is also important for strong bones, prevention of rickets and may even help in preventing some cancers. It should also be noted that many people in the U.S. - older adults, people who are obese, women, and darker skinned individuals - may have lower than what is necessary Vitamin D levels.
The American Academy of Dermatology has reconfirmed the need to boost Vitamin D intake though diet and nutritional supplements rather than UV radiation. Renowned medical experts agree that increasing exposure to UV (either natural or artificial) should not be recommended as a supplemental source of Vitamin D.
Vitamin D is available as a vitamin supplement, and is also available in foods such as fish and fish oil, fortified milk and margarine, egg yolks, liver, Swiss cheese, and fortified breakfast cereals.
If you do spend time in the sun to get your Vitamin D, it doesn't take long. The average person receives enough incidental sun exposure for adequate amounts of Vitamin D. For example, it's possible for a light-skinned person to get adequate Vitamin D by spending 5-15 minutes in the sun without sunscreen, twice each week, with his or her face, arms, hands, or back exposed to the sun. After initial exposure, sun protection, such as cover-up clothes and sunscreen, is important to prevent over-exposure and sunburn.
For more information, check out this article from the World Health Organization: Are There Beneficial Effects of UV Radiation?