Sun-protective rash guards with Ultraviolet Protective Factor (UPF) and wetsuits that block the harmful rays of the sun are the best defense as they do not lose effectiveness in the water. These garments may not cover all exposed skin (face, ears, neck, hands, etc.) so sunscreen is needed as well.
Sunscreen reduces the risk of skin cancer as well as painful sunburns and premature aging of the skin. It is important to always use sun protection as harmful ultraviolet light is present year round, not just in the summer, and penetrates clouds, even on rainy days.
Sunscreen is best applied to all exposed skin 15-30 minutes prior to sun and water exposure. Most people under-apply sunscreen so be sure to use a generous amount!