Carolyn Kaster / AP

You wouldn't believe how many of these guys are missing toenails. Taken at the Marine Corps Marathon in Arlington, Va., Sunday, Oct. 31, 2010.

A few weeks before her first marathon, Kristel Crame bought a trendy purple polish to cover her toenails, one of which she'd bruised on a long training run.

But as she started her at-home pedicure, "I noticed a toenail seemed a bit loose. It seemed like the bottom part was connected and the top part was all lifted up," she said. Even stranger: A new, normal toenail was growing underneath the unhinged one.

This month, as runners across the country put the finishing touches on their marathon-training regime, thousands will share the experience of losing a toenail. Also known as "black toenail" and "runner's toe," it's a harmless occurrence, according to Dr. Marybeth Crane, a Texas podiatrist and board certified foot surgeon who has run dozens of marathons and triathlons over the past 32 years.

For many runners, when the old-and-busted toenail falls off, they find what seems to be a "backup toenail" underneath. But we don't actually  have replacement toenails waiting in the wings: When a toenail is bruised, it stops growing but stays attached.

"We actually have matrix cells in the nail bed, that's where the new toenail comes from, and it literally pushes off the old one" as it grows, Crane explains. The dead toenail stays on to protect the sensitive skin.

Nail bruises can be caused by anything from ill-fitting shoes and socks to a plodding stride or hammer toes. Even perfectly fitted shoes can be a problem: Over the course of a marathon, feet can swell half a size or more.

Crane calls black toenails "one of life's minor annoyances" that can be avoided by keeping toenails clipped, buying long-distance shoes a half-size large and ensuring the toe box accommodates your foot properly.

Though losing a toenail poses no harm, Crane has two important cautions. First: No bathroom surgery. "All of the Internet is going to tell you to light a match on a needle and stick it under the toenail" to drain the bruise. Do that and you’ll likely get an infected, swollen toe that needs medical attention.

Second: If your toenail develops a dark line that does not grow out or disappear, see a doctor right away. "There is a very rare form of melanoma that will happen underneath the toenail" that can be deadly if left untreated.

With all her expertise and precautions, even Crane has lost a few toenails over her decades-long running career: Four, actually. As for Crame -- the runner -- she now coaches beginning marathoners in Seattle, making sure to school them on the art of losing a toenail.

Are you a distance runner who's in mourning over a lost toenail? Do tell. 

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As fall allergies act up or school kids get their first round of seasonal colds, it's not unusual to hear a voice that sounds hoarse or croaky -- what's described as a "frog in the throat."

When Dr. Ramon Franco, director of the division of laryngology at Massachusetts Eye and Ear Infirmary in Boston, hears this complaint he says it can mean one of two things. It can mean a temporary hoarseness when patients try to speak, or people may feel like there's a lump in the throat -- as if they swallowed a frog.

The three main causes of the hoarseness type of "frog in the throat" are viral, allergies, or reflux, explains Franco. Anything that disturbs the opening and closing of the vocal folds (what we commonly call the vocal cords), can deepen your voice and make it sound rough. 

For seasonal allergy sufferers, mucus from the sinuses can make its way into the throat and act as a wedge, interfering with the vocal folds regular opening and closing pattern. This changes the sound of your normal voice so it seems raspy and strained. Sometimes simply clearing the mucus in your throat helps your usual voice return.

During a viral illness, mucus can also clog up the inner workings of the voice box leaving you sounding husky.

If it's not seasonal allergies and you don't have a cold, sore throat, or flu, Franco says the likely culprit is "silent reflux," known as laryngopharyngeal reflux (LPR). Acid from the stomach can come up and hit the bottom part of the throat irritating the delicate voice box. When this happens less than 50 times a day, that's normal. When LPR reflux happens more frequently provoked by such common triggers as spicy foods, alcohol, caffeine, carbonated beverages, and smoking, it can irritate the throat over time.

To defend itself from the acid backwash, the throat blankets itself with a mucus coating. But if too much mucus buildups as a protection against reflux, it may cause excessive throat clearing, a persistent cough, or "a frog in the throat."

A froggy throat is often a temporary annoyance that goes away after a viral illness runs its course or allergy symptoms are relieved. If it's from silent reflux, start by avoiding the dietary or lifestyle habits that trigger acid into the throat.

For a "frog" that feels like a lump in the throat or that something is in there when you swallow, which doctors call the globus sensation, Franco says inflammation is probably responsible. This can be brought on by a bad cold, reflux, a viral infection, allergies, or enlarged tonsils.

But if you've been consistently hoarse and your voice sounds abnormal for more than two weeks, make a doctor's appointment. This could be anything from an infection or polyps to thyroid problems or cancer. If you truly discover a lump in your neck, Franco recommends seeing your doctor immediately to find out what's causing the swelling.

Readers, what's your best remedy for a gravelly voice?

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