Your daily Starbucks run may do much more than perk you up each morning and set you back five bucks. It may actually protect you from getting skin cancer.

A new study backs up previous research that shows caffeine may be an effective weapon in the fight against skin cancer-the most prevalent type of cancer in the United States, according to the American Cancer Society.

In the study, which was published in Proceedings of the National Academy of Sciences, two groups of mice-one genetically modified to block a certain protein called ATR, the other a control group-were exposed to ultraviolet (UV) radiation. The researchers found that the genetically-modified mice remained tumor-free for significantly longer and after 19 weeks of UV exposure, had nearly 70 percent fewer tumors than the control group.

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The research helps shed some light on how caffeine is able to decrease the risk of sunlight-induced skin cancer. Caffeine appears to inhibit the ATR kinase pathway, which plays a major role in how the body responds to DNA damage brought on by UV radiation. ATR obstructs cell division and allows DNA repair to occur rather than letting damaged cells die.

This sounds like a good thing, but, "not all repairs are successful and some cells can still go on to develop cancer," explains study co-author Allan Conney, the director of the Susan Lehman Cullman Laboratory for Cancer Research at Rutgers University School of Pharmacy. "The study we did with colleagues at the University of Washington identified the ATR kinase pathway as being inhibited by caffeine." The result? More DNA damaged cells are killed off, potentially preventing non-melanoma (basal or squamous cell) skin cancer from ever developing.

But caffeine doesn't only inhibit this important protein. Caffeine itself also acts as a sunscreen, absorbing harmful UV rays, according to Conney. So will your sunscreen contain a shot of caffeine one day? "I would think that's a real possibility," he says.

QUIZ: How healthy is your skin?

Until that day comes, there's some good news for coffee drinkers: You're already getting some sun protective benefits from your daily cup of joe. A 2007 study of nearly 94,000 women found that those who sipped caffeinated coffee daily had an almost 11 percent lower risk of non-melanoma skin cancer. Women who drank six or more cups of coffee on a daily basis saw a 30 percent reduction in risk.

(To put that in perspective, a venti size at Starbucks is two and a half cups of coffee.)

Just don't skip the sunblock. "Let's put it this way-you shouldn't start depending on your local Starbucks for sun protection," says Dr. Howard Sobel, a cosmetic dermatologist in Manhattan. "The same general rules apply when it comes to sun protection. Apply a broad-spectrum, water-resistant sunscreen with a SPF of 30 or more to all exposed skin. Look for broad-spectrum on the label, as it provides protection from both ultraviolet A (UVA) and ultraviolet B (UVB) rays. Reapply every two hours, even on cloudy days, and after swimming or sweating. Avoid tanning beds, and have your skin checked regularly by a dermatologist."

By: Rachel Grumman Bender

That's exactly what happened to Brooke Burdine after she popped into her local nail salon for her weekly manicure.

"The next morning my boyfriend looked at me and said 'You look like you got punched in the face," says the 25-year-old marketing exec in New York City, who speed dialed her dermatologist. "The skin around my eyes was reddish-black, and also dry, irritated and itchy."

The diagnosis: an allergic shiner. This not-so-common allergic reaction occurs when blood around the eyes is unable to drain so it stays put and causes the appearance of a bar-fight-style black eye.

Usually it's from an out-of-control pollen count that causes sinuses to swell, not from getting your nails done. "The doctor asked me what new products I was using-cleanser, eye cream, makeup, detergent-and I couldn't think of anything in my routine that I'd changed," Burdine says. "But the possibilities seemed endless because he also explained that I could not be allergic to something and then develop an allergy overnight."

After discussing a laundry list of suspects, Burdine's doctor glanced at her freshly painted nails and noted that he has a lot of women come in because of allergic reactions to polish, which are laced with potentially toxic chemicals including formaldehyde.

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And since Burdine wears contacts and is often touching her eyes, the polish could be the culprit. "That's when I realized that although I've always gone to the same salon and use the same brand of polish, that time I grabbed one from a company I've never used before," she says. Her doctor told her to take the polish off asap and apply Desonide, a prescription steroid cream, around her eyes to reduce the swelling in that area. "In two days I was back to normal," she says.

According to Julia Liou, cofounder of the California Healthy Nail Salon Collaborative, a public-advocacy group for salon safety, Brooke isn't alone. The fight for safe nail practices and products for both technicians and customers is crucial because of a slew of health hazards -- sure, a freaky black eye is one, but extreme medical conditions such as reproductive issues and cancer may also be real concerns.

Although the dangers of many chemicals used in nail products (including remover, base and top coat as well as polish) are proven and many brands are going 3 and 4-free, experts say there's still good reason to think twice before test-driving a neon pink half-moon manicure.

MORE: 3-free and 4-free nail polish, explained

"Companies are saying they're taking the harmful chemicals out-formaldehyde, toluene and DBP-but no one is regulating whether or not it's true," says Liou, who estimates about 40 percent of polish on the market are 3-free, while the other 60 either aren't or have varying levels of toxic ingredients.

It's this nail industry "he-said, she-said" along with the fact that cosmetic companies aren't required to get the green light on safety from the FDA, and most nail brands don't list ingredients on their bottles like say, shampoo, that has many organizations pushing for the Safe Cosmetics Act.

This bill would demand pre-market safety assessments of all personal care products-not just nail polish. (As of right now, the Safe Cosmetics Act is expected to pass early next year.)

MORE: The Safe Cosmetics Act and what it means for your makeup bag

According to Cora Roelofs, an occupational health researcher at the University of Massachusetts Lowell, who has studied the long-term effects nail chemicals and fumes have on salon workers, many report rashes on their cheeks and hands-possibly as a result of sensitization (like getting an allergy) to acrylic compounds such as ethyl methacrylate, the main ingredient in artificial nail liquid-but all solvents such as isopropyl alcohol as well as acetone can cause rashes just by taking the natural protective oils out of skin. She also adds that nail technicians experience an abundance of respiratory problems including coughing, nose, throat and lung irritation, asthma and wheezing.

Could second-hand nail service fumes be the new second-hand smoke? Clearly, the salon workers exposed to hazardous chemicals and fumes 10 hours a day are at the most risk, but a weekly half-hour polish pit-stop can add up. "A salon might be using 3 and 4-free brands, but there are still so many different kinds of solvents in formulas as well as a lack of fresh air and a lot of dust," says Roelofs.

According to the experts interviewed, Burdine's black eye is definitely not the norm, however, doctors agree that allergic reactions from nail products and services are not only possible, they're common. "Typically, people are most allergic to chemicals in acrylic nails-from the polymers in the nails themselves to the gel and glue-which might be laced with poisonous methyl methacrylate liquid monomers (MMA), but also formaldehyde in nail hardeners and polish as well as fumes from acetone," says D'Anne Kleinsmith, M.D., a dermatologist in West Bloomfield, Michigan. "These chemicals might cause contact dermatitis-the skin right around or underneath the nail can get red, itchy or scaly."

MORE: The best non-toxic nail polishes

But eyes are also at risk. "The eyes are a sensitive, exposed organ," says Elise Brisco, M.D., an optometrist in Los Angeles and founder of the Rehabilitative Vision Clinic at the Cedars-Sinai Medical Center. "Bacteria, viruses, allergies, pollen and chemicals all stick to the wet, mucous-y surface which is very absorbent-and what's scary is that the eye is essentially an extension of the brain." Brisco suggests that if you have any pain in or around your eyes, blurred vision, stinging, swelling or redness for more than a few hours after leaving a nail salon, to see your doctor.

Now, take a deep (fume-free) breath: Experts insist that you don't have to ditch your weekly mani and succumb to hiding your bare, chipped nails in shame: "Common sense and precaution says that if it's not necessary to be exposed to toxic chemicals (and it's hard to imagine when it is necessary) then these chemicals should not be in products at all," says Roelofs. "But in the mean time, choose a well-ventilated salon if you're concerned."

QUIZ: How healthy does your skin look?

Also, be aware of what products the salon you're frequenting is using. "I've seen a tremendous change in the nail industry," says Jin Soon Choi, a manicurist for 20 years and owner of Jin Soon Nail Salon in New York City. "The old style strong-fumed acrylic is almost gone, non-acetone nail polish remover is ubiquitous and there are amazing 3 and 4-free polishes."

And of course ladies, (you gotta) fight for your right (to a healthy manicure). Take action at safecosmetics.org.

By: Genevieve James

Anyone who has ever pounded the pavement in strappy sandals knows that, by dusk, your soles are the color of the asphalt you've been strolling. We won't even get into the "tan line" of grime around your ankle strap.

After finding out what your feet have picked up -- a seriously unappetizing stew of germs -- you may be ready to ditch your Havaianas for a pair of knee-high boots.

"When walking on the street in something like a flip-flop, you are exposing your foot to vomitus, human waste, dog feces, sputum expectorated by people -- some of whom may have microbacteria -- and a wide variety of other things like food or liquids that have been brewing in the hot sun," says Philip Tierno, Ph.D., director of clinical microbiology and immunology at New York University Langone Medical Center and author of "Secret Life of Germs."

The kind of cooties you find on city streets, he says, include norovirus (that scourge of cruise ship passengers), staph aureus, types of strep, E. coli and drug-resistant superbugs like Pseudomonas, Klebsiella pneumonia and MRSA. "The summer heat," he adds, "acts like an incubator."

If your feet have cuts or open blisters, you may unknowingly be laying out a welcome mat to the viruses and bacteria stuck to the street. But even if you're abrasion-free, you can transfer all of that nasty stuff the moment you handle your flip-flops when you slip them off or drop them in your bag to change into heels.

Explains Tierno, "You're exposed to something even worse -- these organisms on your hands." According to Dr. Tierno, 80 percent of all infectious diseases are transmitted by direct or indirect touching -- kissing or picking up a dirty shoe -- then touching your eyes, nose or mouth

But before you reserve a spot in the nearest plastic bubble, there is good news. "Your skin is built to protect you from getting infected by its very nature," says Jeannette Graf, M.D., assistant clinical professor of dermatology at Mount Sinai Medical Center in Manhattan. The dead skin layer known as the stratum corneum is thickest on the hands and feet and is considered your body's first line of defense. "Our skin makes antimicrobial peptides that fight against bacteria and viruses and lots of different pathogens," explains Dr. Graf.

And there are several steps you can take to prevent your tootsies from transferring germs to your hands. Shoe designer Matt Bernson, whose creations are worn by actress Amanda Seyfried and model Gisele Bündchen, has a suggestion for the legions of women who swap out their shoes when they arrive at work or home: "Carry your shoes in a shoe bag when they are in your purse."

To banish germs, use good old-fashioned soap and water. "You want to wash your feet when you get home," says Dr. Graf. Or in a pinch, apply an antibacterial hand sanitizer on your feet, she suggests. Also, park a pair of slippers by the front door. "In general, it's not a good idea to come into your home with dirty shoes that have walked on every known substance and schmear it all over your house," says Tierno.

You can help keep your skin's protective barrier in peak condition by exfoliating dead skin cells and slathering on moisturizer, says Dr. Graf. Gently smooth rough spots and calluses with a foot file or pumice stone, such as Sally Hansen's Prep your Pedi Foot File or Pumice Foot Polish -- not with one of those callus razors, says Ji Baek, founder of RescueBeauty.com and author of Rescue Your Nails. "They're illegal in many states," says Baek, and they can cut your foot way too deeply. "It's better to use a foot file and liquid soap when you get home at night."

Or try a homemade foot soak and scrub. Donna Perillo of Manhattan's Sweet Lily Natural Nail Spa adds warm citrus juice (grapefruit or orange) to a foot soak. "The acidity kind of eats at the grime," she says. Follow that up with an all-natural sugar scrub, which you can make at home using granulated sugar, olive oil and your favorite essential oil. And then apply moisturizer.

Dr. Graf recommends using a lotion with skin-smoothing lactic or salicylic acid or urea before bed each night. Or you can lightly coat your feet with Vaseline petroleum jelly and then slip on cotton socks, such as Moisture Jamzz socks to protect your sheets. You'll wake up with super-soft, germ-free feet.

By: Maria Ricapito

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