What Causes White Spots on Nails and How to Prevent Them

Here's something you probably don't do very often: Take a good long look at your fingers. See any white spots on your nails?

Perhaps you've heard that these white marks are a sign of a vitamin or mineral deficiency. But it turns out that most white spots on fingernails aren't related to nutrient consumption, per the National Health Service.

These marks are known as leukonychia, according to the Cleveland Clinic. And while they're usually harmless — often caused by everyday activities or minor injuries — there are a few things you should know about them.

Leukonychia, the condition where white spots appear on your nails (this can be your fingernails or toenails), is very common and generally not a reason for concern.

The term "total leukonychia" refers to the condition when a fingernail or toenail is entirely white, instead of the pinkish color that this part of the body tends to be, according to DermNet NZ, a resource supported by the New Zealand Dermatological Society.

"Punctate leukonychia" refers to the condition when there are white dots or marks on one or more nails, but the pink part of the nail is still visible.

Leukonychia can affect people of all ages.

There are plenty of reasons a person may spot leukonychia on their nails. One of the most common reasons is trauma to the nail plate, which can occur from nail-biting, manicuring, pedicuring, hitting or banging the nails or wearing tight shoes, per DermNet NZ.

These white spots tend to go away over time as the affected nail grows — this tends to take anywhere from six to nine months.

Total leukonychia may occur after a more serious injury to the nail.

In some cases, the white spots on your nails could be a sign of an allergic reaction to a certain polish you've applied to your nails, according to RajaRajeswari Medical College and Hospital.

The occasional white fleck on your nail isn't a cause for concern, but persistent white spots on fingernails, or splotches ⁠— more serious versions of leukonychia ⁠— can be related to secondary health issues. White spots on nails can sometimes be related to health issues like psoriasis or chronic kidney disease, per the Cleveland Clinic.

When these white spots or blotches appear in your nailbed or are emerging as your nail plate grows, this may be a sign of a more serious, systemic health issue, according to an April 2015 study in the ‌Indian Dermatology Online Journal.‌

Because white spots on the nails are rarely cause for concern and usually caused by minor physical trauma to the hands and nails, you don't need to be particularly worried about preventing them.

Still, if the marks are aesthetically displeasing to you, there are a few measures you can take to reduce the likelihood of their appearance.

If you suspect your nail polish may be the culprit, stop using the polish for a few weeks to see if this reduces the appearance of white spots.

Think about the times you're most physical with your hands. Are you washing the dishes without rubber gloves? Could you be more cautious when it comes to closing the car door? Does your weight-lifting routine need to be a bit more gentle on your digits?

Consider the physical movements throughout your day that may lead to stress and trauma in the nails, and then work through some solutions that may protect your nails when you perform these activities in the future.

White marks on nails should not be confused with nail pitting, which are depressions or indented spots on the surface of the nails, per the Mayo Clinic.

While nail pitting isn't caused by vitamin deficiencies either, it can be related to other health problems, including psoriasis, psoriatic arthritis, dermatomyositis, syphilis, sarcoidosis and pemphigus vulgaris, per a March 2016 review in the ‌Indian Dermatology Online Journal‌.

Pitting typically occurs in people who have immune system issues, including autoimmune diseases like alopecia areata, pemphigus vulgaris or lupus, or inflammatory diseases like sarcoidosis, arthritis or dermatomyositis.

However, pitting can also occur in relation to a range of other problems, including connective tissue disorders like Reiter's syndrome, syphilis and psoriasis.

While white lines or spots on nails don't usually signify a nutrient deficiency, there are some other nail conditions that can sometimes serve as a clue.

In rare cases, onychoschizia, or the condition of brittle or splitting nails, may be a sign of an iron deficiency, according to the American Osteopathic College of Dermatology (AOCD).

While white spots on nails aren't likely to be related to vitamin or other nutrient deficiencies, white lines or ridges might be, according to a May 2012 study in the ‌Indian Journal of Dermatology, Venerology and Leprology‌.

Nutrient deficiencies can cause ridges or lines on your nails. Deficiencies in zinc, calcium, folic acid and protein can affect the nails and cause lines to form, according to the research in the ‌Indian Dermatology Online Journal‌.

Other types of nutrient imbalances can cause different types of white marks on nails or even completely whitened nails, per research in the ‌Indian Dermatology Online Journal‌. For example, a lack of selenium may lead to completely white fingernails. Such issues can often be easily resolved by eating more foods with selenium or taking selenium supplements.

A registered dietitian can help you determine which nutrients you may be lacking in your diet and whether taking a vitamin or supplement may be right for you.