Brittle, splitting, peeling, and cracking nails — they’re enough to drive a woman crazy. Make that one in five women, which is how many dermatologists estimate suffer from this collection of symptoms called brittle nail syndrome (also referred to as onychoshizia by the med­ical community).

Brittle nails are sometimes linked to health conditions such as hypothyroidism and menopause. Some medications, including diuretics used to treat high blood pressure, also can promote brittle nails, as can deficiencies in iron and vitamins A, C, and B6. The condition also sometimes accompanies skin disorders such as eczema, lichen planus, and psoriasis.

Even with all these possible causes, it’s safe to assume your client’s brittle nails are most likely caused by external factors such as excessive handwashing or wet work. According to the American Osteopathic College of Dermatology (AOCD), internal disease or vitamin deficiencies are rarely the cause of brittle nails. “One tip is that if the fingernails split but the toenails are strong, then an external factor is the cause,” states the AOCD.

Regardless of contributing factors, explains Richard Scher, M.D., professor of dermatology and head of the section for diagnosis and treatment of nail disorders at Columbia University-Presbyterian Medical Center in New York, dehydration lies at the root of all brittle, splitting, and fragile nails. “The average amount of moisture in a normal nail plate is 18%,” Dr. Scher explains. “When the moisture dips below this level, the nails become brittle.”

Brittle nails can occur at any age, but the condition is more common in children with eczema and in older women. “Both the skin and the nails become drier with age,” says Dr. Scher. “Also, with older people there is actually as much as a 30%-40% reduction in the nail growth rate. This means that the nail material at the free edge is older, and therefore drier. Reduced or poor circulation to the fingers further accentuates the drying effect.”

It seems contradictory that wet work can dehydrate nails, but Dr. Scher explains that it’s constant wetting and drying that weakens the nail structure. “Frequent handwashing causes the nail cells to swell and contract repeatedly,” he says. “It is as if a piece of wood is bent back and forth many times — eventually it will break. The same thing happens to the nails.”

Low humidity and dry heat tends to worsen the condition, as does cold weather.

“Cold weather can wreak havoc on your client’s hands and nails,” says Dr. Scher. “Special care must be taken during the winter months to combat the associated nail problems.” Nail techs can recommend liberal use of moisturizers and gloves during cold snaps.

Call in the Reinforcements

As complex as its causes, caring for brittle nail syndrome is relatively simple. Start by urging clients to wear gloves when using cleaning agents and detergents. Next, educate them on protecting their nails from trauma and resisting the temptation to use them as tools.

The AOCD recommends combating brittle nails by soaking the nails in water for five minutes each day and then generously applying an AHA-or lanolin-based lotion. They also should reapply the lotion every time their hands get wet.

Urge clients to minimize water exposure by wearing gloves to perform household chores.

Debunk the nail-strengthening myths of gelatin and calcium. Neither do anything to strengthen the nails, regardless of whether they’re taken as supplements or applied in fortified nail treatments. “Calcium is not in nails,” explains Zoe Diana Draelos, M.D., a cosmetic dermatologist in High Point, N.C.

As for gelatin, says Dr. Scher, “People have always looked for an easy way to strengthen the natural nail plate. Nails are made of a protein ... and a deficiency of protein can show up as soft, fragile, or brittle nails. Since gelatin is a form of protein, the logic is that the protein would help to strengthen nails.” However, no proof exists that gelatin does anything to strengthen nails.

As far as what the nail tech can do, Dr. Scher cautions against excessive mechanical manipulation. Exert only the gentlest pressure on the cuticles and nail plates with implements such as cuticle pushers to avoid damaging the nail matrix. Also, avoid contact with the nail plate with all but the finest-grit files to avoid further shredding and delamination of natural nail layers. By the same token, make liberal use of buffers. The gentle friction will stimulate blood circulation in the capillary-rich nail matrix and bed.

Next, recommend nail treatments and polish as temporary reinforcements. The protection they offer is fairly minimal because water can be absorbed into the nails from the underside and any other exposed portion of the natural nail, but Dr. Scher says treatments do appear to helpminimize shredding and breaking.

Some nail techs and clients swear by formaldehyde-based nail treatments, but Dr. Draelos says they ultimately make nails even more brittle. “They’re not a good idea,” she says.

Caution clients that polish is more likely to chip and advise them to apply a fresh coat over existing layers every two to three days. Because polish removers dehydrate the nails, treatmentsand polishes should be removed no more than once a week. Dermatologists recommend acetate-based removers, which are believed to be less dehydrating than acetone-based.

Even with all of these protections, most clients with brittle nail syndrome need to keep their nails short. If clients desire longer nails, artificial enhancements present their best option.

Going for the Cure

Clients who want a miracle cure will want to learn more about biotin, one of the minor B vitamins. Biotin’s role in human health isn’t entirely understood, but studies have shown that the vitamin can thicken weak nails and reduce splitting in as little as six to eight weeks.

Biotin first was used to treat the cracked hooves of thoroughbred racehorses in the 1980s. It proved so successful that a group of Swiss researchers set out to test the theory on women.

Thirty-two women participated —10 with normal nails and 22 with brittle nails. Eight of the 22 women with brittle nails took a daily biotin supplement for at least six months, while the other 14 women were administered biotin irregularly throughout the study. The results were impressive: Researchers found that the thickness of the nails in women who took daily supplements increased as much as 25% and that they experienced less splitting. The group who took irregular supplements also enjoyed significant, though far less impressive results: Their nails thickened an average of 7% and they, too, had less splitting.

Under Dr. Scher’s direction, the nail research center at Columbia University in New York City initiated a similar study of biotin. “We were able to confirm their results in two out of three patients, a somewhat lower success rate... but nevertheless impressive,” he says.

Biotin is found in most multivitamins in minute quantities, and it’s also contained in eggs, organ meats, legumes, cauliflower, broccoli, and mushrooms. Researchers don’t understand how biotin works to repair brittle nails and cracked hooves, but Dr. Scher says it appears to be safe, with no known side effects.

Biotin is available without a prescription from health food stores and pharmacies, and Dr. Scher sees no harm in nail technicians discussing biotin with clients. However, he advises nail techs to refer clients to their family doctor for dosage recommendations.

Finally, send clients with brittle nail syndrome home with a copy of a “Caring for Brittle Nails” client handout but only after you book their next appointment in a customized “nail-strengthening regimen” personally designed by their nail care professional.

A Client’s Guide: Caring for Brittle Nail Syndrome

If you suffer from brittle nails that tend to split, peel, and crack, know that you’re not alone. According to dermatologists who specialize in nail disorders, 20% of women suffer from brittle nail syndrome.

Many factors can set up the conditions for brittle nail syndrome — including health conditions such as hypothyroidism as well as medications for high blood pressure and deficiencies in iron and some vitamins — but at their root, brittle nails are caused by dehydration of the nail plate.

The normal nail comprises as much as 18% water (in contrast to the body’s 70%). Frequent handwashing or exposure to detergents and other cleaning agents can dehydrate and weaken the nail structure.

“Frequent handwashing causes the nail cells to swell and contract repeatedly” explains Richard Scher; M.D., professor of dermatology and head of the section for diagnosis and treat­ment of nail disorders at Columbia University-Presbyterian Medical Center in New York “It is as if a piece of wood is bent back and forth many times — eventually it will break. The same thing happens to the nails.”

Low humidity and dry heat along with cold weather also can make nails brittle. While there’s no complete cure for brittle nails, there are many steps you can take to protect them and promote healthy growth.

Moisturize your cuticles and nails with an AHA-or lanolin-based lotion after every handwashing. Before bed, soak your nails in warm water for five minutes and liberally apply moisturizer Consider cotton-lined spa gloves for sleeping.

Wear gloves for dishwashing and other “wet work.” Cotton-lined rubber gloves work best. Give your nails a bonus by applying moisturizer before donning your gloves.

Cover up with nail treatments or polish. Avoid formaldehyde-based products because they will further dry out the nail, but other treatments can provide some protection to nails.

Go easy on the polish remover. Choose acetate polish removers over acetone-based ones because they are less drying and limit their use to no more than once a week.

Skip the gelatin and calcium supplements in favor of biotin. Researchers say biotin, a minor B vitamin, can strengthen nails by as much as 25% and reduce splitting.