This article was medically reviewed by Caroline Chang, MD, a board-certified dermatologist and member of the Prevention Medical Review Board, on September 24, 2019.
Yellow nails are where it’s at when you’re in the mood for a bright and cheery manicure—but when your digits are giving off a lemony vibe and there’s not a drop of nail polish on them, it could be your body’s way of hinting that something’s off.
“Like growth rings of a tree, marks on your nails represent changes in your health over time,” says Joshua Zeichner, MD, director of cosmetic and clinical research in the department of dermatology at Mount Sinai Hospital. “If your nails turn yellow, it may be as simple as a nail polish staining the nail plate. However, there may also be an infection or an underlying disease that’s causing them.”
Any changes to your nails where the underlying culprit isn’t obvious or that seem to be sticking around—color changes, thickening, crumbling—should be evaluated by your dermatologist in case there’s a medical issue that needs to be addressed, says Dr. Zeichner.
The sooner you nail down the cause of your tinted fingertips (pun totally intended), the sooner you can get your nails—and possibly your health—back on track.
As for what might be causing your yellow nails? Here are seven possible culprits that dermatologists were kind enough to share dirt on:
1. You love wearing dark nail polish.
Wearing nail polish on the regular (especially darker shades) can stain your nails yellow. “The dye in the nail lacquer interacts with the keratin of the nail, causing a yellow discoloration and brittleness,” says Philadelphia-based dermatologist Rina Allawh, MD. Acetone nail polish remover can worsen the yellowing by giving the dissolved nail polish a chance to bond to your nails like a stage five clinger.
Since the yellowing typically strikes the upper part of the nail, the best way to get your nails back to normal would be to take a breather from polish and allow the stained portions to grow out.
To prevent yellow nails from happening in the first place, apply a clear base coat before your polish and switch up your go-to colors so you’re not using dark polishes as often, says Dr. Allawh. Investing in a non-acetone polish remover can also be helpful in keeping yellow stains at bay.
2. A fungal infection might be lurking.
When a pesky fungus invades the nail (usually toenails), it can lead to thickening of the nail itself and accumulation of debris underneath—both of which can lead to a yellow color, says Dr. Zeichner.
Your dermatologist can culture the nails to determine the exact type of fungus, and tailor your treatment according to what would work best to combat it—say, a topical or prescription antifungal medication.
“Because nails grow slowly, a systemic medication would need to be prescribed for 3-6 months in order to fully eradicate the fungal infection,” says Susan Massick, MD, a dermatologist at The Ohio State University Wexner Medical Center. (The only bummer is that cure rates with current antifungals are generally 50 to 60 percent, so repeat treatments may be necessary.)
3. You work with your hands (a lot).
When the end of your nail separates from the nail bed, this is known as onycholysis.
“Because a space develops underneath the nail, it gives off a yellow or opaque appearance,” says Dr. Zeichner. It’s commonly seen in people who work with their hands, such as hairdressers, manicurists, food handlers, and cleaners. (It can also be caused by trauma, psoriasis, and as a side effect of certain medications, says Dr. Massick.)
To treat it, it’s important to cut off the part of the nail that’s separated from the nail bed. “The separation creates a space underneath the nail that allows microorganisms to grow and prevent the nail from reattaching,” says Dr. Zeichner, who recommends soaking your nails in Listerine twice daily. “Listerine contains an ingredient called thymol that’s anti-microbial and will help the nail reattach as it grows back in,” he says.
Avoid further trauma to your nails by wearing protective gloves, steering clear of wet environments and harsh chemicals, and keeping your nails trimmed, says Dr. Massick. Cleaning under your nails can also make onycholysis worse by causing it to move further back on the nail bed. (Same goes for using your nails as a tool, such as to open pop cans.)
If you think your yellow nails might be related to medications, consider chatting with your doc about discontinuing what you’re on, especially if your nails become bothersome or painful, says Dr. Massick.
4. It could be a sign of a vitamin deficiency.
“Malnutrition can affect growth of the nails, and in some cases, lead to a yellow discoloration,” says Dr. Zeichner. Your doctor may run blood tests and evaluate you for vitamin and nutrient deficiencies, like zinc or b12. “If you do have a deficiency, then use of supplements over several weeks to months may help correct the deficit,” adds Dr. Zeichner. Over time, your nails should get back to their regularly scheduled programming.
5. You’re a smoker.
Yellow nails and fingers are both telltale signs that you’re a smoker or used to smoke, according to the American Academy of Dermatology. This is caused by the repeated exposure to the tar in tobacco smoke. Your nails may also take on a rounded or clubbed appearance, which can occur from chronic lung disease or COPD in long-term smokers.
You may also develop something known as the Harlequin nail, which specifically refers to the appearance of a nail after someone quits smoking suddenly because half the nail is stained and the other half (the new nail that grows in during smoking cessation) is not stained.
6. ...or a fan of self-tanners.
Self-tanning products contain an ingredient called DHA. “It reacts with your skin cells to leave behind a yellow-orange color that mimics a tan,” says Dr. Zeichner. If it gets on your fingers as you apply it, it may accumulate at higher levels around your cuticles and give your nails a dark yellow appearance. If you suspect your self-tanner might be the cause of your yellow nails, either vigorously wash your hands to remove any excess product after you’ve applied it, or consider wearing gloves during the application process.
7. It may actually be hereditary.
There’s a rare condition that’s actually called yellow nail syndrome—it can happen randomly and may run in families. Along with yellow toenails and fingernails, you may experience respiratory breathing problems, chronic sinusitis, and swollen legs. It usually strikes in middle age, but can happen when you’re younger too, according to the Genetic and Rare Diseases Information Center.
Your dermatologist will confirm the diagnosis through a nail clipping (to rule out fungal elements), blood work, a physical exam, and a detailed clinical history, says Dr. Allawh. You’ll then be referred to a specialist who will treat the specific breathing and swelling problems you may be experiencing, as well as your nail issues.
8. An underlying health issue may be to blame.
Thyroid disease may lead to nail issues like yellowing, thickening, and crumbling of the edge of the nails. Diabetes can cause yellow nails too: “It’s unclear why, but it may have to do with high-circulating sugar levels,” says Dr. Zeichner. (Because people with diabetes may experience a compromised immune system, this can also increase the risk of developing a fungal nail infection.)
“For both of these health issues, your doctor will do some blood tests to evaluate for any thyroid issues or diabetes,” says Dr. Zeichner. “Close management of these conditions may, in time, improve the appearance of the nails.”
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