What Your Nails Reveal About Your Health

Remember Madge, the manicurist and perky lady on TV who touted the benefits of soaking your hands in Palmolive dish soap? I still love getting manicures and pedicures, walking out of the salon with shiny crimson nails like those of Cleopatra and Queen Nefertiti.

We all know the many ways to learn about our health – think blood pressure measurements and EKG readouts – but did you know that looking at your nails can give clues about what's happening inside your body?

"Many nail findings occur in the absence of any kind of systemic (internal) cause. However, when there are obvious changes in the nails, whether fingernails or toenails, there are a number of potential medical causes a physician must consider," says Chris G. Adigun, M.D., a dermatologist and nail specialist in Chapel Hill, North Carolina.

Nails are composed of layers of alpha-keratin, a protective protein material that also makes up the cells in our skin and hair. Cuticles are layers of dead skin cells that seal in moisture and prevent the entrance of germs. Fingernails protect both the fingertips and the surrounding soft tissue. Problems with the nail bed, the nail itself, or the areas around the nail can indicate only a localized issue (as in nail fungus) or a more systemic one. 

"Nail problems make up about 10% of all dermatologic conditions, increasing with age and affecting a significant number of older adults," says Maral Kibarian Skelsey, MD, founder and Director of the Dermatologic Surgery Center of Washington and a Clinical Associate Professor of Dermatology at Georgetown Medical School in Washington DC.

Fingernail growth slows down as we get older. Age-related changes in the nail plate include thickness, contour, surface and color alterations. Brittle nails, splitting and ridging of the nails, nail thinning or thickening and severely peeling nails can occur, and the frequency of nail fungus increases with age. 

Oral medication is the most effective for nail fungus, especially for thickened nails, and should be accompanied by topical treatment. Brittle nails respond to "manicure vacations," nail rehydration regimens, or in severe cases, prescription medicated lacquers such as Nuvail or Genadur. Poor nutritional status and diets low in protein can result in thin, brittle nails. 

Many different types of medications, including those used by older adults, can affect nail growth, health and appearance, explains Skelsey. Culprits can include anti-seizure drugs, antidepressants, retinoids, antibiotics, antivirals, anticoagulants and chemotherapy agents. 

While most nail changes do not indicate illness, some can be related to underlying medical conditions. Spoon-shaped (convex) nails, known as koilonychia, can be associated with iron deficiency anemia, Raynaud's Phenomenon, psoriasis, celiac disease and other systemic diseases. 

They can also result from occupational hazards, such as hairdressers' hands being exposed to chemical irritants like hair dyes or repeated exposure to water in food service and health care workers, says Adigun. 

Clubbing (thickening of the tissue at the base of the nail) is seen in people with lung diseases such as severe asthma or COPD (chronic obstructive pulmonary disease), cardiothoracic and inflammatory bowel disease.

"Lifting" nails (onycholysis) can be a sign of hypothyroidism but is more commonly associated with water exposure or aggressive manicure techniques. Ridged or cracked nails can indicate a deficiency of B-complex vitamins, calcium or omega-3 fatty acids. Horizontal ridges, known as Beau's lines, can result from a high fever, injury or peripheral vascular disease.

Pitting (nail plate indentations) can sometimes be seen with psoriasis or other conditions, including autoimmune diseases and connective tissue disorders. Up to 90% of people with psoriatic arthritis (a type of arthritis found in people with psoriasis) have nail involvement affecting both toenails and fingernails. These changes can include discolorations, ridging, thickening and crumbly appearance. Treatments for nail psoriasis can include topical steroids and a vitamin-D-based treatment. 

Nails almost completely white can be a sign of liver disease or diabetes. White spots on nails (keratin granulomas) are generally not problematic, even though many people erroneously think they're related to vitamin deficiency. 

According to Adigun, the most common cause is trauma to the nail as it is being developed, so a small "bang" to the end of your finger can lead to a small white spot in the nail as it grows out. "This is because the matrix underlies this skin, and it is the delicate apparatus in charge of building the nail," she explains. Nail fungus can also cause powdery white spots.

Redness of the moon-shaped portion of the nail bed (the lunula) can be seen with heart failure. Yellow Nail Syndrome can be due to lung disease such as pulmonary effusion or bronchiectasis, but it is more often caused by staining from polish.

Green nail syndrome indicates the presence of a pseudomonas nail infection, a bacterium found in wet environments such as hot tubs and sinks. A bluish tint to nails can mean the body isn't getting enough oxygen and can indicate a cardiac or lung problem and a vitamin B12 deficiency. 

Medications, hormones or moles can cause long brown or black vertical lines or stripes. They could also indicate subungual melanoma, a form of skin cancer under the fingernail. Squamous cell carcinoma, also a skin cancer, typically appears as a red, erosive mass that disrupts nail growth. 

"Neapolitan nail," found in about 20% of people over age 70, involves a distinctive nail discoloration associated with osteoporosis or a collagen abnormality for some. If you are a character in a murder mystery and notice blue half-moons or Mees' Lines - white bands transversing the nail bed - you should be wary because these can be signs of arsenic, thallium or heavy metal poisoning.

Frequent gel manicures can cause thinning and damage to the nail because of the trauma of removing the gel. Radiation from UV nail polish dryers can damage DNA and potentially increase the risk of skin cancer, says Skelsey, who suggests wearing sunscreen or fingerless gloves when under UV light. Other suggestions include:

• Wear gloves when working with your hands, including housework, gardening and house repairs. Cotton gloves provide better protection than latex gloves.
• When getting manicures or pedicures, use a licensed salon that properly sterilizes equipment or, better yet, bring your own set of tools.
• Don't let a nail tech push back or cut your cuticles, which increases the chance of infection or inflammation.
• Take periodic mani-pedi vacations and allow your nails to go au naturel.
• Avoid keeping nails wet for prolonged periods since chronic moisture can lead to infections.
• Wear flip-flops in public places to decrease exposure to athlete's foot, a fungal infection that can spread to the toenail.
• To help prevent ingrown toenails, wear well-fitting shoes and trim nails straight across. 
• If you have diabetes, see a podiatrist for foot care as recommended, and always keep your feet clean and dry.

Barbra Williams Cosentino RN, LCSW, is a psychotherapist in Queens, N.Y., and a freelance writer whose essays and articles on health, parenting and mental health have appeared in the New York Times, Medscape, BabyCenter and many other national and online publications. Read More