Does semi-permanent nail polish damage the nails?

Having nails that are impeccably colored and do not chip is the dream of nail polish enthusiasts. Semi-permanent options are appealing for this as they withstand climate changes, UV rays, humidity, and impacts. This manicure technique is performed with an acrylic gel mixed into a polish that does not air dry but hardens when exposed to a UV or LED lamp. Specifically, a photopolymerization reaction occurs within the semi-permanent polish. The application of this type of polish can be done at home or in a salon and takes about 30 to 45 minutes. The result then lasts for several weeks. Another advantage of semi-permanent polishes is that their use is now widely democratized and they come in numerous versions. The semi-permanent polishes thus present themselves as an interesting option for those wanting a long-lasting and resilient manicure.

Despite their numerous benefits, semi-permanent polishes are not without consequences for nail health, particularly when used repeatedly or removed without caution.

Indeed, the unique formulation of semi-permanent nail polishes, which contributes to their longevity, may not necessarily be beneficial for the nails. As mentioned earlier, this type of polish is composed of acrylic polymers and hardens under the action of UV or LED light through a photopolymerization mechanism. However, by creating a solid and adherent layer, this reaction also forms a nearly hermetic barrier on the nail surface. Although it cannot be said that this prevents the nail from breathing — nails do not breathe in the literal sense as they do not facilitate any gas exchange — this prolonged occlusion can lead to an increase in its moisture content, making it soft and fragile. Indeed, when the keratin in the nail absorbs too much water, it swells, causing the layers that make up the nail to separate and potentially split. This issue, already posed by traditional nail polishes, is amplified by semi-permanent polishes, which create a much stronger barrier.

Beyond their resilient texture, semi-permanent nail polishes contain reactive molecules that can weaken the nails and surrounding skin. Among the commonly used molecules are methacrylates, such as hydroxyethyl methacrylate (HEMA), trimethylhexyl dicarbamate (DI-HEMA), and hydroxypropyl methacrylate (HPMA). These are essential to the photopolymerization process but they are also known to be potentially irritating to the skin and nails, causing redness and itching.

Furthermore, the removal of semi-permanent nail polish can also weaken the nails. Indeed, to remove a semi-permanent polish, one must combine mechanical sanding with the use of acetone. However, while this molecule is effective in removing polish, it also dissolves some of the protective lipids of the skin and nails. Additionally, when done improperly, sanding can sometimes be too abrasive and damage the initial layers of keratin, making the nail thinner and more susceptible to damage. This step can also create small ridges on the nail surface. That's why it's often recommended to entrust the removal of a semi-permanent polish to a professional in a salon.

To limit the damage to nails caused by semi-permanent polish, it is recommended to take breaks of about two weeks between each polish application. In the meantime, take the opportunity to hydrate and nourish your nails, using a vegetable oil for example.

Note : The potential damage to nails is not the only concern raised by semi-permanent nail polishes. Like traditional nail polishes, some formulas may contain formaldehyde, dibutyl phthalate, or even parabens, all of which are suspected to be endocrine disruptors at high doses or with chronic use.