The Environmental Working Group released its annual sunscreen report this week, and the news is not good: Researchers recommended only 8 percent of beach and sport sunscreens — 39 out of the 500 analyzed.

EWG says that most sunscreens have the potential to do more harm than good because they carry exaggerated SPF claims (50 and up) that don't offer much increased protection, and may contain potentially hazardous ingredients — like a form of vitamin A called retinyl palmitate, found in 41 percent of sunscreens because it's an antioxidant that slows aging. Says EWG:

"The FDA is investigating whether this compound may accelerate skin damage and elevate skin cancer risk when applied to skin exposed to sunlight. FDA data suggest that vitamin A may be photocarcinogenic, meaning that in the presence of the sun's ultraviolet rays, the compound and skin undergo complex biochemical changes resulting in cancer [...] In FDA's one-year study, tumors and lesions developed up to 21 percent sooner in lab animals coated in a vitamin A-laced cream (at a concentration of 0.5%) than animals treated with a vitamin-free cream. Both groups were exposed to the equivalent of just nine minutes of maximum intensity sunlight each day. [...] The evidence against vitamin A is far from conclusive, but as long as it is suspect, EWG recommends that consumers choose vitamin A-free sunscreens."

The irony of a sunscreen that might cause skin cancer being lost on nobody, I contacted Marie Jhin, MD, a dermatologist and adjunct clinical instructor at Stanford University. "As far as I know, there is no definitive research stating that topical vitamin A causes skin cancer," she says. But we don't know for sure that it doesn't cause skin cancer, either, so a little precaution may be warranted. "I recommend more physical sunblocks that don't contain large amounts of vitamin A anyway," Dr. Jhin adds. "And I do believe that many sunscreens have over-hyped marketing. Higher SPF does not mean it is a better sunblock or better protection."

Worried about what you'll be slathering on to protect your skin at your Memorial Day BBQ this weekend? Click here to find out how your sunscreen, or SPF-containing lip balm, moisturizer and makeup rated. Then check out EWG's Sunscreen Hall of Shame for the worst offenders and click here for a list of the safest brands.