Four out of five sunscreen brands don't live up to their promises

The Environmental Working Group, a Washington-based nonprofit, has released an investigation of nearly 1,000 brand-name sunscreens that says four out of five don't adequately protect consumers and may contain harmful chemicals.

The group says some of the products of the nation's leading brands -- including Coppertone, Neutrogena and Banana Boat -- are the poorest performers.

Coppertone was named by the Environmental Working Group as having 41 products that failed to meet the group's criteria for issues ranging from failing to protect adequately to containing potentially harmful ingredients to making unsubstantiated claims. But in a statement to CNN, the company says it "rigorously tests all its products in the lab and in the real world," to ensure they're safe and effective.

Neutrogena says its sunscreen products have been "embraced by dermatologists and consumers for their efficacy," and says its new Helioplex technology provides broad-spectrum UV defense against sun damage.

The science of sunscreens is simple: Active ingredients are compounds that absorb, reflect or block ultraviolet light. Sunscreens are regulated by the Food and Drug Administration not as cosmetics, but over-the-counter drugs. Sunscreens are rated based on their SPF, or "Sun Protection Factor." The higher the SPF, the better the protection against sunburn.

The Environmental Working Group says the SPF rating on a sun product is only part of what consumers need to know, and one of the biggest problems with sunscreens is that they don't fully protect against sunlight.

"A good, effective sunscreen must prevent against a broad spectrum of rays," says Sonya Lunder, a senior researcher at the Environmental Working Group.

Sunlight is composed of two types of ultraviolet light -- UVB rays, which cause sunburns, and UVA rays, which tan. While both may increase the risk of skin cancer, sun damage and wrinkles, the FDA doesn't require sunscreens to protect against both, just UVB.

The FDA acknowledges new rules mandating UVA testing and labeling requirements are being evaluated, but the Environmental Working Group wants tougher standards now.

"The fact most sunscreens still don't don't offer UVA protection and the fact the FDA has been working for years to finalize its rules is really what provoked us to look at this issue," Lunder says.

If you are sensitive to sunscreen, never go without. Instead, try sunscreens that provide a physical barrier, such as zinc oxide or titanium dioxide. New micronizing technology makes both appear more transparent on the skin, so you don't have to look like a lifeguard with a white nose.