As the warmer spring and summer months approach, it's tempting to make plans for long weekends at the beach or days lying on a picnic blanket in the park. Especially since sunlight has proven benefits on mood, says Dr. Kishwer Nehal, a director of dermatologic surgery at Memorial Sloan-Kettering Cancer Center in New York City.

However, all those hours in the bright sun can add up to a large increase in the risk of skin cancer. Are those shiny, happy days really worth the health risks?...