The Food and Drug Administration recently decided to enter the fray in the discussion of sunscreen. In Summer 2012, their findings and rulings will be displayed on every bottle of sunscreen that claims to block the sun. Sunscreens that boast SPF, or sun protection factor, tend to filter only UVB light, which is what causes sunburn. But a shield for UVA light is needed as well - UVA light contributes to skin cancer, wrinkles and other age-related skin conditions. The new FDA rule will require any sunscreen labeled "broad spectrum" to protect against both UVA and UVB rays. Another somewhat surprising development is the discovery that no matter what the bottle says, no sunscreen is waterproof. The best a sunscreen can claim under the new labeling rules is being "water-resistant." Sunscreen does wear off after sweating and swimming, so you should reapply every couple of hours anyway, even if you use those brands labeled for sports or ones that use the terms "sweatproof" or "waterproof."