Is Nail Polish Bad for Your Nails?

Q: I keep my nails near-constantly polished, but I worry that it’s damaging them. Do nails need breaks or time to “breathe”?

The idea that your nails need to “breathe” is actually a myth, said Dr. Chris Adigun, a dermatologist in Chapel Hill, N.C., who specializes in nail disorders.

“Your nails don’t have lungs,” she said.

However, there are some signs that your nail polish, or the way you remove it, may be causing changes to your nails that should prompt a break, experts said. And it’s important to inspect your nails between polishes so you can spot any potentially worrisome shifts that might be occurring underneath the color, Dr. Adigun said.

Here’s what to watch out for.

Is nail polish bad for your nails?

In short, no, said Dr. Adam Rubin, a dermatologist and nail specialist at N.Y.U. Langone Health.

There’s nothing in traditional nail polish that will directly harm your fingernails or toenails, he said. But, he added, there are some cosmetic issues that may crop up if you keep your nails painted for too long, such as for several weeks at a time.

Some nail polishes — dark or red colors, in particular — can stain the surface of your nails, Dr. Rubin said. This isn’t harmful, but you might not like the way it looks, he added.

Leaving polish on for too long may also dry out your nails, causing chalky, white patches to form on their surface, said Dr. Anisha Patel, a dermatologist at MD Anderson Cancer Center in Houston.

Those patches, called keratin granulations, are benign and more commonly found on toenails, which are typically painted for longer than fingernails, Dr. Adigun said. They can sometimes be mistaken for a nail fungus called white superficial onychomycosis.

If you notice either staining or white patches after removing your nail polish, there’s no harm in disguising the discolorations by painting over them, Dr. Rubin said. If you do that, though, know that you risk making the stains or white patches worse.

To completely banish these issues, let your nails regrow fully, unpainted. This can take about six months for fingernails and 12 to 18 months for toenails, Dr. Adigun said.

To prevent staining or white patches from forming in the first place, it can help to apply a clear base coat before you paint your nails. Massaging moisturizer onto your nails and cuticles between polishes might also help keep keratin granulations from forming, Dr. Rubin said.

If you remove your polish and your nails look dry, moisturize them daily, whether they’re polished or not, Dr. Patel said. You can use petroleum jelly, hand cream, nail oil or body lotion, Dr. Rubin suggested.

What actually will damage your nails?

The way you remove nail polish, on the other hand, can damage your nails, Dr. Rubin said. Scraping or picking at nail polish can strip the top layers of the nail and possibly lead to thinning. And acetone-containing nail polish removers can dehydrate and damage your nails, he said, so it’s best to use nail polish removers that are acetone-free.

This is one reason dermatologists typically urge caution with gel manicures. The removal process usually involves soaking your nails in acetone, which can lead to dryness and brittleness, Dr. Adigun said. The gel polish itself can also cause allergic reactions (like a rash or, more rarely, hives) and damage the nails. And exposure to ultraviolet light during the application process can increase your risk for skin cancer and premature skin aging, according to the American Academy of Dermatology.

If you do get gel manicures, give your unpainted nails a break of at least a week or two between manicures to let your nails recover, Dr. Adigun said.

When should you worry?

Every time you remove nail polish, examine your nails for potentially worrisome changes, Dr. Adigun said.

Dark streaks, splitting, lifting from the nail bed and pain are all potential signs of skin cancer, so if you notice those, visit a dermatologist, Dr. Patel said.

Thickened, crumbly, yellow or misshapen nails can signal a fungal infection, Dr. Rubin said. And redness or swelling around your nails could indicate an injury or bacterial infection, according to the A.A.D. Tiny dents or pits in your nails; crumbling; nails separating from your skin; or white, brown or yellow discoloration could be signs of nail psoriasis.

When patients come in with worrisome nail problems, they often wonder if it’s because of their nail polish, Dr. Rubin said. But that’s usually not the case. They just may not have noticed the changes forming over time, “because the nail polish was covering their nails,” he said.

Dermatologists recommend annual skin cancer checks, and that includes examining the nails, Dr. Patel said. “We ask our patients to come in without polish on at least once a year so that we can see their nails,” she said.