How long can you keep nail polish on without it causing damage?

The idea that your nails need to “breathe” is a myth, says Dr Chris Adigun, a dermatologist in Chapel Hill, North Carolina, who specialises in nail disorders.

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

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 says. And it’s important to inspect your nails between polishes so you can spot any potentially worrisome shifts that might be occurring underneath the colour, Adigun says.

Here’s what to watch for.

If you keep polish on your nails for weeks at a time, you may notice some cosmetic issues.Credit: Getty Images

Is nail polish bad for your nails?

In short, no, says Dr Adam Rubin, a dermatologist and nail specialist at NYU Langone Health.

There’s nothing in traditional nail polish that will directly harm your fingernails or toenails, he says. But, he adds, 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 colours, in particular – can stain the surface of your nails, Rubin says. This isn’t harmful, but you might not like the way it looks, he adds.

Leaving polish on for too long may also dry out your nails, causing chalky, white patches to form on their surface, says 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, Adigun says. They can sometimes be mistaken for a nail fungus called white superficial onychomycosis.

If you notice either staining or white patches after removing nail polish, there’s no harm in disguising the discolorations by painting over them, Rubin says. 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, Adigun says.

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, Rubin says.

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

It can take between 12 and 18 months for toenails to regrow.Credit: Getty Images

What actually will damage your nails?

The way you remove nail polish, on the other hand, can damage nails, Rubin says. 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 nails, he says, 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, Adigun says. The gel polish itself can also cause allergic reactions (like a rash or, more rarely, hives) and damage nails. And exposure to ultraviolet light during the application process can increase your risk for skin cancer and premature skin ageing, 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 nails recover, Adigun says.

When should you worry?

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

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, Patel says.

Thickened, crumbly, yellow or misshapen nails can signal a fungal infection, Rubin says. And redness or swelling around your nails could indicate an injury or bacterial infection, according to the AAD. 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 nail problems, they often wonder if it’s because of their nail polish, Rubin says. 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 says.

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

The New York Times

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