Summertime means emerging from your dimly lit cubicle to expose your pallid skin to some precious rays of sunshine. But that presents you with a sticky dilemma: Slather yourself in UV-fighting goop or increase your chance of skin cancer (just five sunburns doubles your risk for melanoma). Fortunately for heliophiles, Neutrogena scientists developed this formula, which is based on something the company calls Micromesh technology. Instead of having that Tacky Glue–like consistency, this stuff is lightweight yet still shields your epidermis from harmful rays as you sweat through your beach volleyball game. It’s supposed to keep you cooler, too, but it’s not magic: You still have to reapply at least every two hours.

Avobenzone

The two main types of skin-damaging UV radiation are UVA and UVB. Avobenzone absorbs the former, which accounts for about 95 percent of the UV radiation that reaches Earth and also penetrates the skin more deeply (yikes, wrinkles!). Trouble is, once this stuff gets hit by sunlight, it changes into a form that’s power­less against UVA. But octocrylene comes to the rescue.

Octocrylene

This oily liquid is a stabilizer, helping keep avobenzone in a form that can continue leading the fight against UVA.

Tocopheryl Acetate

As UVA rays penetrate the skin, they can cause oxidative stress: The light beam forces bonds between molecules to break unevenly, sending atoms with unpaired electrons careening into the body. To stop these unstable free radicals from stealing electrons from other molecules, which could wreak havoc on cell structures and DNA, this ­vitamin E–based antioxidant donates an electron to neutralize the thieves.

Acrylates/Dimethicone Copolymer

This film-forming agent, found in many cosmetics, helps the UV-fighting ingredients spread evenly. Fun fact: Dimethicone is the key to Silly Putty!

Silica

Similar to what’s in those “Do Not Eat” gel packs, this airy mineral soaks up residue like a sponge, preventing the lotion from leaving a slick sheen. (Much of the product is basically water trapped in oil.) After application the H 2 O evaporates, creating micro­channels that allow sweat to escape—Neutro­gena’s so-called Micromesh technology. The company claims that the resulting evaporative cooling lowers skin temps by about 3 degrees Fahrenheit.

PEG-30 Dipolyhydroxy­stearate

This emulsifier keeps the ingredients suspended in solution. It’s responsible for CoolDry’s delicate, nongreasy finish. PEG compounds also ensure uniform distribution in other toiletries like toothpaste—but please do not brush your teeth with sunscreen.