What Are the Causes of Splitting and Peeling Nails?

**About 20 percent of the population has brittle nails, characterized by nails that split or peel into layers, according to a June 2018 review article in “Journal of Dermatological Treatment.**” Also known as onychoschizia, splitting and peeling nails tend to become more common with age.

Splitting and peeling nails are most often due to too little or too much moisture in the nails, trauma to the nails or a fungal nail infection. These causes tend to affect just one or some of the nails.

Various vitamin deficiencies and medical disorders can also produce splitting and peeling nails. Because they begin as an internal problem, these causes are more likely to affect most or all of the fingernails and toenails.

How Moisture Affects Splitting and Peeling Nails

Most instances of splitting and peeling nails are caused by lack of moisture, according to the American Osteopathic College of Dermatology (AOCD). Repeatedly wetting and drying the hands — and therefore fingernails — can cause the nails to become dried out and brittle.

Hand sanitizers containing alcohol also tend to dry out the hands and fingernails. Dry nails are more common when the air is dry, such as in the winter.

Less commonly, fingernails can be too moist. This produces soft nails that are also prone to peeling 8.

Fingernails can be protected from becoming wet by wearing gloves for activities in which the hands are immersed in water, such as washing dishes.

AOCD recommends applying a moisturizing lotion containing alpha-hydroxy acids or lanolin to help prevent or treat dry and brittle nails. Limiting the use of alcohol-based hand sanitizers may also be helpful.

Can Nail Trauma Lead to Splitting and Peeling Nails?

Why Do My Fingernails Peel & Break?

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Injuries to the nails can cause splitting and peeling. Nail biting leaves fingernails ragged and prone to additional damage. Using the fingernails as tools for scraping and prying will also cause nail injuries.

Typing produces repeated trauma to the nails, especially when they are long. Nails can also be damaged during grooming activities, such as using metal instruments to push back cuticles.

Keeping nails trimmed short and filing them with an emery board into a rounded shape may help reduce splitting and peeling. Short nails can also reduce nail trauma while typing.

Avoiding the use of nails as tools and being gentle when performing grooming activities are other useful strategies.

Applying a coat of clear nail polish once a week may help protect nails from injury, according to AOCD. Polishes containing nylon fibers are preferred, as they may also strengthen the nails.

Can Everyday Chemicals Damage My Nails?

Household cleaning fluids or detergents may dry out or directly damage the surface of nails, leading to peeling and splitting.

Colored nail polish, adhesives used for glue-on nails and nail polish removers may also cause nail damage. Removers containing acetone are more likely to harm nails than acetone-free nail polish removers.

The effects of chemicals on nails can be reduced or eliminated by limiting exposure to the chemicals. Wearing rubber gloves during household cleaning activities will help protect fingernails. Adding a moisturizer to the nails after each chemical contact may also be useful.

Can Nail Infections Cause Splitting and Peeling?

Weak Fingernails

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Fungal infections of the nails frequently cause splitting and peeling 6.

They are more common in the toenails than fingernails and usually affect one to a few nails at the same time. The nails become thicker but more brittle.

Fungal nail infections are often recognized by the typical color changes they produce, causing the nail to become yellowish or light brown.

Fungal infections are more likely to occur in nails that have been injured and in people with diabetes, poor circulation in their feet or a weakened immune system, according to the Centers for Disease Control and Prevention (CDC) 6.

As fungi grow best in moist environments, walking barefoot in locker rooms or public shower areas increases the likelihood of getting a fungal infection. Several over-the-counter medications are available to treat fungal nail infections, but prescription medications are sometimes needed.

Which Medical Disorders Can Split and Peel Nails?

A number of medical disorders may cause peeling and splitting nails. One of the most common is hypothyroidism — an underactive thyroid gland, which causes the nails to become thin and dry 2.

Other possibilities are blood vessel disorders affecting the feet or hands, psoriasis, diabetes, sarcoidosis and Sjorgren syndrome. All of these conditions produce other symptoms as well.

Chemotherapy medications and certain pills used to treat acne may also cause peeling and splitting nails.

Can Nutrient Deficiencies Affect My Nails?

Iron deficiency can produce brittle nails 3. Nail changes usually do not occur until iron deficiency is severe enough to also cause anemia — low numbers of red blood cells in the body 3.

Iron deficiency anemia may produce various symptoms, including pale skin, headaches and pica — an unusual craving for non-nutritive substances, such as ice or dirt 3. Iron-rich food or iron supplements will reverse the deficiency.

Biotin deficiency may also cause brittle nails that peel and split. True biotin deficiency is rare, however, because biotin is found in a large number of foods and the body needs only a small amount of biotin.

But even in people with normal biotin levels, biotin supplements may help brittle nails. Current research suggests that daily biotin supplements improve hardness, thickness and firmness of brittle nails, according to a June 2018 review article in “Journal of Dermatological Treatment. 11”

When to See a Doctor for Splitting and Peeling Nails

If you have brittle nails, see your doctor to help determine the cause and begin appropriate treatment. As the cause is often related to moisture or trauma, simple measures may be all that are needed.

But if you have a fungal infection, your doctor will likely recommend an antifungal medicine. Your doctor can also determine whether your nail problems are a sign of a medical disorder or nutrient deficiency.

Reviewed and revised by Mary D. Daley, M.D.