The latest wave of sunscreens relies on new formulations of good old zinc oxide and titanium dioxide

The UV Wave of the Future: What's on the horizon?According to dermatologist Laurie Polis, it's taking vitamin C or beta-carotene pills—"to protect your skin not only from without, but from within."

Gone are the days of "that St.-Tropez tan." You remember the ad: a heartthrob male voice trebling, "If I could set the world on fire," a bronzed model with a gold chain-call it a waistlet-draped across her belly. These days, even Bain de Soleil comes in SPF 28. (It still looks like orange petroleum jelly, by the way.)

Though bronzing, burnishing, and shimmering via cosmetics are all very much the rage, actual tanning is outré. The zeal for tanning has been replaced with the zeal for finding natural, eco-friendly ways to prevent sun damage: sunblocks whose active ingredients are minerals like titanium dioxide or zinc oxide, FDA-approved for screening UV rays. These compounds, which are less harmful to ocean and lake waters than their synthetic or organic chemical counterparts (think about all those SPF 30 slicks you leave behind every time you take a dip), have always been common ingredients in diaper creams. As New York City dermatologist Laurie Polis put it, "when an ointment is gentle enough to spread over a newborn's bottom, you know it must be safe."

Zinc oxide is the stuff you used to see striping the noses of lifeguards and old-time sailors. It came in the medicinal-looking tube that was so easily mistaken for toothpaste; worse, the cream was a Colgate look-alike that must have SPF-ed many a molar. Once they're rubbed into the skin, the new formulations of zinc oxide and titanium dioxide are transparent-yet, like their predecessors, they physically block the sun's ultraviolet radiation just as a tightly woven shirt does. By contrast, organic chemical sunscreen agents such as the newly touted Parsol 1789 absorb and alter UV rays. The drawback to these potions is that they can cause allergic reactions.

Titanium dioxide and zinc oxide sunblocks are already flooding the shelves. Some of the standouts are Murad's Murasun Daily Sunblock, a light, milky lotion that smells faintly like poster paint-not unpleasant, actually-and Peter Thomas Roth's water-resistant Titanium Dioxide Sunblock, which leaves your skin feeling just slightly damp, not at all oily. Physicians Formula's Sun Shield Extra Sensitive Skin Formula, also water-resistant, is glorious: it has an utterly natural scent-like sunbaked clay-and an almost powdery finish. Christian Dior's Ultra-UV Coat for the Face includes chemical sun filters along with titanium dioxide-but it can be forgiven, because its pink and white container is so damn cute.

One caveat: Though zinc oxide and titanium dioxide act as a physical barrier, they must, unlike clothing, be reapplied periodically. This is a warning for those who think SPF 30 makes them invincible. In fact, the SPF number corresponds to the length of time you would normally go unburned without protection: if you burn in 5 minutes, with SPF 30 you can stay in the sun safely for 30 times 5 minutes.

But there is hope for tanning enthusiasts: those fair-skinned Russians still aspire to "set the world on fire." Since 1993, their space program has made several attempts to unfurl a huge reflector in space that will beam the sun's rays onto swaths of Russia 24 hours a day to shed a little light on the long, dark winters. They last tried (and failed) in February. But they're determined to keep on trying. Who knows?Maybe they'll be the first to come out with SPF 288.

Jessica Dineen is an associate editor at Travel & Leisure.

Faking It
We understand that you don't want to come back from your vacation in St. John as pale as when you left, nor do you want to spend all your Caribbean hours getting fried poolside or nursing a second-degree sunburn indoors. There is, thankfully, a better way. Self-tanners have evolved since the orange-streaked days of the 1980's—now they look way more natural, and they're moisturizing as well. Our editors logged many hours trying out the latest lotions, gels, and sprays, as well as older favorites. Here are our picks for the best, bar none.
1. Decleor's Self-Tanning Cream is the ultimate for natural-looking color, even on the most ghostly person in the office. (Me, in case you're wondering.) For a blissful bare-legged summer, this SPF 4 product moisturizes with shea butter, doesn't have that telltale tanner smell or cloying sticky feeling, and really lasts.
2. Botanical Self-Tanning Lotion from Sisley leaves skin looking sun-kissed, not dyed. The sage extract and marjoram oil have a divine scent, but at this price—$78 for one ounce—you'll want to save it for your face.
3. When you have the need for speed, only Guerlain's Terracotta Self-Tanning Emulsion will do. Formulated to work from the moment of application, this lotion has a pearly sheen, perfect for a last-minute night out on the town.
—Kimberly Robinson