What if you could take a pill to help protect you from the harsh effects of the summer sun? Now you can--though don't toss out your sunscreen and hat, because you're still going to need them.

The pill, called Heliocare, is made of the extract of a fern grown in Honduras, where it has been used to treat skin conditions for hundreds of years (it's been available in Europe for 30 years as well). Skeptical? Small studies published in the Journal of the American Academy of Dermatology have shown that the fern, whose scientific name is polypodium leucotomos, reduces the cancer-causing and aging effects of ultraviolet radiation on skin, including DNA damage, inflammation, immune system suppression, and collagen breakdown. This year, supplements containing the extract became available in the United States for the first time. "The data showing its effectiveness is there," says David Leffell, a professor of dermatology and medicine at Yale School of Medicine.

The pills are intended to supplement, not replace, sunscreen, and can benefit everyone, dark- and fair-skinned alike. The product is sold at major drugstore chains, where you'll pay approximately $60 for 60 pills.

Even though the new pill is useful, it doesn't let you off the hook with sunscreen. Sunscreen is the one thing you really can't cheat on in your sun-protection regimen, especially if you're going to be out between 10 a.m. and 4 p.m., when the sun is at its strongest. (You'll need sunscreen at other hours as well, since UVA rays are as strong earlier and later in the day as they are at noon.) Slather it on at least 20 minutes before you head out the door, and reapply every two hours, as well as after you've been sweating or in the water. Use a sunscreen with a sun protection factor (SPF) of at least 15, which blocks 93 percent of the sun's rays. Higher SPFs don't give you much extra protection. An SPF of 30, for example, blocks 96.7 percent. To get the full protective effect of a sunscreen, you need to put enough on: For an average-size person, the equivalent of a shot glass full each time. "If you're going to the beach for a week, you should easily go through a whole bottle," says Tina Alster, a Washington, D.C., dermatologist and professor at Georgetown University.

The SPF on the tube refers only to the sunscreen's ability to screen out ultraviolet B rays that cause visible sunburn and are strongest during the hottest part of the day. But experts now know that ultraviolet A rays, which don't vary by time of day or season and are the main culprit in aging skin, also cause skin cancer. But there's no FDA-approved standard for UVA protection, so you need to look at the ingredients on the back of the tube. Sunscreens containing avobenzone, titanium dioxide, or zinc oxide block rays in the ultraviolet A spectrum. This year, Neutrogena came out with a line of sunscreens using "Helioplex" technology that it claims makes the UVA blocker avobenzone last up to several hours without losing its effectiveness. "I think Neutrogena has the best technology that's available today," says Susan Weinkle, a dermatologist and assistant clinical professor at the University of South Florida in sunny Tampa. You'll pay about $11 for 4 ounces; Neutrogena is widely available at drugstores.