The Mavala Stop no-bite polish has denatonium benzoate, also known as the brand name Bitrex, that causes an intensely bitter taste.Courtesy Mili Godio
I've been biting my nails for as long as I can remember. It started when I was at the age when copying my parents (who also incessantly bite their nails) was my most important day-to-day task. It naturally evolved into a nervous habit once I reached my teenage years, when homework, extracurriculars and friend group drama was top of mind. Now, as an adult, I constantly find myself nervously biting at my nails (and even the skin around it) without even thinking. Frankly, it's embarrassing, annoying and unattractive.
I've tried many different ways to stop nail biting over the years: painting my nails, using a nail strengthening serum, even redirecting my anxiety to a stress ball or silly putty. I've tried (and failed) to rid myself of the habit for years and nothing ever seemed to work until I tried a bitter-tasting top coat that made me never want to put my hands near my mouth ever again.
The Mavala Stop Deterrent Nail Polish has been the only thing that actively stops me from biting my nails. The bitter taste of the polish is too awful and overpowering to fight through, and even putting my fingers near my mouth immediately causes me to recoil. Below, I share more about my experience using this to kick my nail-biting habit.
SKIP AHEAD What is the Mavala Stop no-bite polish? | How I use the Mavala Stop no-bite polish | Is no-bite nail polish safe? | The bottom line | Why trust NBC Select?
The Mavala Stop polish looks like clear nail polish -- it comes in a small bottle with a brush applicator that you swipe on your nail. However, it has a very bitter taste and smell, and has a thin consistency (rather than the thick, heavy feel you'd expect from a typical nail polish). The primary goal is to significantly reduce the number of times you put your fingers in your mouth and it's specifically made to kick habits like nail biting and thumb sucking.
The polish has a mix of ingredients including ethyl acetate and butyl acetate, which are common solvents found in nail polish, and isopropyl alcohol (also known as rubbing alcohol). The polish has denatonium benzoate, also known as the brand name Bitrex, which is what causes the intensely bitter taste. (It smells like hand sanitizer or nail polish remover, in my experience). These ingredients are safe for both adults and kids 3 years or older, according to the brand and experts I spoke to (more on that below). Mavala doesn't recommend this polish for younger children because their taste buds are not yet fully developed and they may get used to the bitter taste.
I first bought this no-bite polish in March 2024 and have used it nearly every week since then. It goes on completely clear and looks like my natural nail with a slight shine when I apply it, so I can wear it under regular nail polish, as a top coat or on its own.
The best part about this nail polish is that I don't have to use it every day -- though the brand recommends reapplying every two days, I've noticed that once I swipe it on my nails, the product (and the bitter taste) usually lasts well over a week. Now, I reapply it every one to two weeks. When I do need to reapply, I remove the previous coat with a regular nail polish remover.
Admittedly, I do fall back into the nail-biting habit if I forget to reapply the polish, which has happened a couple of times since I started using it. The polish also doesn't stop me from picking at my nails (though I do get the polish on my fingers, which later impacts some foods I pick up with my hands), so I do need to pair it with other tools like a fidget toy or pick pad if my anxiety levels are high.
The nail polish actively stops me from biting my nails better than any other method I've tried. Here's why I think it's the best option for those in a similar boat as me:
As with any habit that spans decades, I unconsciously repeat the behavior -- in this case, I touch my nails to my teeth or pick at the skin around my fingernails. Fortunately, the bitter taste this clear polish yields is very strong, as if I were putting a hand sanitizer-soaked cotton ball on my tongue. The bitterness coats my mouth and hits my taste buds almost immediately. Best (or perhaps worst) of all, that taste lingers for at least 15 minutes after accidentally putting my fingers anywhere near my mouth.
However, that also means it comes with a few drawbacks: The bitter taste transfers a bit to finger foods, so if I'm eating certain snacks like chips, carrots and cookies, I will sometimes taste the bitterness if my fingers come too close to my mouth. It's not always the case, and the strength of the bitterness fades the longer I wear the polish.
My favorite part about this polish is that it requires very little maintenance and effort. Since it dries clear, I don't have to be precise about how I'm applying it or worry about how it'll look. Plus, a little goes a very long way: one or two swipes of the polish is more than enough. It stays on my nails for over a week, so not only does it not feel like a chore to keep reapplying it, but I've also barely made a dent in the bottle over the past five months.
I have the 10-milliliter bottle, which is slightly skinnier and shorter than a typical nail polish bottle (currently, the 5-milliliter bottle is in stock, which is about half the size and more travel-friendly). It's easy to throw in my purse or work tote, which is especially useful if I'm traveling and need to reapply it, or if I expect to be in a stressful situation that might trigger my nail-biting, like participating in a work meeting, getting on a plane or commuting on the subway.
The short answer is yes, according to Dr. Ginger King, a cosmetic chemist at Grace Kingdom Beauty in New Jersey.
The Mavala Stop polish has a typical ingredient list for nail polish, with the exception of added denatonium benzoate for the bitter taste, says King. Like regular nail polish, it also has solvents like alcohol. "[The ingredients are] generally okay, especially since it's to prevent biting, so [it's] not going to be ingested," says King. In fact, the bitter-tasting ingredients are sometimes found in oral medicine to prevent misuse, so it is generally regarded as safe, she says.
The polish does have benzophenone-3, also known as oxybenzone, which studies show can have health and environmental effects at high concentrations (the ingredient is typically found in sunscreen). It can also be harmful for children at high concentrations, says King. (Benzophenone-3 is low on the ingredients list, which means there isn't a high concentration of it.)
Keep in mind that excessive use of this polish, like applying multiple coats on a daily basis, can dry out your nails, says King. The ingredients can also irritate sensitive spots like the eyes and mouth, so don't rub around these areas with your fully-polished fingernails, she says.
This Mavala Stop no-bite polish is, in my experience, the most effective product I've ever tried to stop my more 20-year nail-biting habit. It has a strong, bitter taste and lasts typically over a week with every application. After five months of consistent use, my small bottle still looks practically full. If you struggle with biting your nails and nothing else has worked so far, this nail polish is what you need.
I am an updates editor at NBC Select who frequently reviews products including meal delivery services and Loop earplugs. I've used the Mavala Stop Deterrent Nail Polish every week for over five months and have successfully stopped biting my nails.