Our fingernails can offer up many clues about our health and lifestyle. That's because, just like our skin and hair, our fingernails are always growing. And when our bodies are under stress, there may be signs of it in our nails.

"There are a lot of things that can cause changes in the nail," says Dr. Scott MacLean, a family physician in Edmonton. Fingernails can develop ridges, spots, thickness, splitting and pitting. While some of these changes are nothing to be concerned about, other abnormalities can suggest underlying health problems.

Take comfort in knowing that in most cases of serious disease, you'll notice other symptoms too. "It's not super common that the nails are the only finding," says MacLean.

So what are your fingernails trying to tell you?

Yellowing, thickening and crumbling
Fingernails that are yellow or whitish, thickened and crumbling or splitting could be afflicted with a fungal infection. They often, but not always, follow a case of athlete's foot.

"Fungal infection usually affects the feet, but it can show up on hands as well," says MacLean, who adds that it's probably the most common nail change he sees in his practice. If this description sounds like your nails, ask your doctor about antifungal creams or medications.

Pain or swelling
Tender puffiness around or underneath the fingernail could be nothing more than the aftermath of a hangnail. There's no need to see a doctor unless it doesn't clear up over the next couple of days or if there are several fingers affected.

"If you've got only one nail bothering you, there's a good chance it's going to resolve on its own," says MacLean. However, an untreated infection can spread. Reduce your risk of infection by avoiding artificial nails, nail-biting and careless clipping.

Page 1 of 3 -- Learn what else your fingernails say about your health on page 2

Changes in colour
A black or purplish bruise under the nail might look dramatic. Not to worry, it will fade as it heals. But if you see dark discoloration and you don't remember doing any damage to your finger, then you should see a doctor to rule out skin cancer. If your nails are almost always covered by polish, be sure to remove it once in a while so you can inspect what lies beneath.

Pitting and dimpling
Several skin disorders can prompt some pretty odd indentations in your nails. These include psoriasis, lichen planus, dermatitis and dozens more. But it's not likely that the symptoms would show up only in your fingernails.

"Usually the person knows that they have connective tissue disease or psoriasis and start to notice their nails are affected," says MacLean.

"If they're already seeing a physician for the underlying disease they can bring it up as a new finding."

Brittle nails
Dry, brittle nails aren't normally signs of a serious health problem. But that doesn't mean they don't have something to say. They could be telling you they're overexposed to strong detergents or chemicals.

"We see brittle nails frequently in people who get manicures," says MacLean. If your nails are brittle, avoid wearing nail polish or at least take periodical time-outs and use a nail polish remover that's free of acetone, which can be drying to your nails. Use moisturizer on your hands, and avoid strong soaps and soaking your hands in water.

Clubbing
Clubbing is a condition in which your fingertips gradually get larger and your fingernails curve over them. It's most often linked to low blood oxygen from heart or lung diseases such as emphysema, lung cancer or cystic fibrosis. It sounds serious, but only very rarely would you have nail clubbing without other symptoms.

Page 2 of 3 -- find out what little white spots and thickening nails say about your health on page 3

Little white spots
Little white spots on your nails are called leukonychia. They're common and they're almost always caused by a minor bash or smash to your fingers. They're nothing to worry about unless they don't start to go away after a few weeks.

"Usually you'll see it grow out," says MacLean, "so if that white spot isn't disappearing over time, see a doctor."

Ridges and thickening
"Just aging itself can cause changes in the nails," notes MacLean. Fingernails can become thicker, ridged, more brittle or darker in older people, especially if their bodies' circulation isn't top-notch.

Young or old, you can maintain the health of your fingernails by keeping them clean and dry, and avoiding biting or picking at them. And any time you're not sure what your fingernails are telling you, ask your health-care professional the next time you have an appointment.

"When you're in, you can ask your doctor to look at your nails, if you've seen changes," says MacLean.

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