There are many reasons why your toenails may turn yellow. The most common causes are fungal infections and staining from the dyes in dark nail polish. You may also notice that as you get older your nails start to look yellow, thick, and brittle, and grow more slowly. This is believed to be caused by a natural decrease in blood flow to the hands and feet as you age—it happens to most people.
People who smoke are more likely to develop yellow nails. It’s also more common in people with certain diseases, such as diabetes and thyroid disease. In rare cases, the discoloration is caused by a condition called yellow nail syndrome, which also affects your respiratory and lymphatic systems.
Depending on what caused your nails to turn yellow, you may notice other changes in your nails, such as thickening, brittleness, and splitting. You may be able to treat these symptoms yourself, but there are times when prescription medications are necessary.
People often think that vitamin deficiencies can cause yellow nails. There is not much evidence to support this claim—do not worry about stocking up on supplements. —Dr. Priya Gimbel
1. Fungal infection
- Yellow nails (most often the big toenail but it may affect other toenails)
- Nail thickening
- Brittle nails
- Split nails
One of the most common causes of yellow toenails is a fungal infection of the nails. They are more common in men. You can get these infections from contact with fungi in the environment, often from public spaces where people go barefoot, like gym locker rooms and pools. It’s also possible to develop yellow toenails if you have another fungal infection, such as athlete’s foot, that has spread to your nails.
People with other nail diseases like psoriasis, or conditions that weaken nails like diabetes, are also more likely to develop these infections. Injuries that make it easier for the fungus to get into the nail may also put you at risk.
Treating fungal infections
Fungal infections are hard to treat and often come back. There are home remedies you can try, such as applying over-the-counter anti-fungal creams or solutions that contain clotrimazole or undecylenic acid. Or you can use Vicks VapoRub on your nails instead: Some studies have shown that its ingredients—eucalyptus oil, camphor, and menthol—can help.
If you don’t see an improvement after a month of using at-home treatments, see your doctor or a podiatrist, who can prescribe a topical solution or a pill to treat it. It often takes several months to a year to get rid of the infection.
Do not feel disheartened if you have a fungal infection in your toenail. It does get better, but it may take some time. Many of my patients have noticed improvement over several months, so just keep in mind that there is no quick fix for this. —Dr. Gimbel
2. Nail polish
- Yellow nails after removing nail polish
Wearing toenail polish can cause yellowing because of the stains left behind by the dyes. This is more likely to happen if you use darker shades of nail polish, but yellow, orange, or red polish may also turn your toenails yellow. It’s also more likely if you do not apply a clear base coat under the darker shades.
Treating nail polish stains
Staining from nail polish may go away on its own within a few days, but it can also last longer depending on the type of polish and the color.
To help make the discoloration go away faster, try soaking your nails in a diluted mixture of hydrogen peroxide and warm water (3 tablespoons of hydrogen peroxide in ½ cup of warm water) or a diluted white vinegar solution (1 tablespoon of vinegar in 1 cup of warm water). Soak for 5 minutes and then scrub with a toothbrush to remove the pigment from your nails. Be careful not to soak your nails in pure hydrogen peroxide or vinegar as this can be damaging to your skin and nails.
- Yellow discoloration of the nails
- Nail thickening
- Brittle nails
It’s not unusual for nails to start to look different as you age. It is believed that this happens because of decreased circulation to the hands and feet, which reduces oxygen flow to the feet and causes nails to become discolored, thick, brittle, and slow growing. Age-related yellowing usually affects all of your nails.
Treating age-related yellow nails
This type of yellowing is normal and cannot be treated.
- Yellowing nails
- Nail thickening
- Brittle nails
Like aging, smoking causes a decrease in circulation to your hands and feet, in this case by causing inflammation and plaque build-up in your blood vessels. This causes your nails to turn yellow and change in texture.
Treating yellow nails caused by smoking
If you stop smoking, you may be able to reverse or slow the progression of your circulation problems and improve the condition of your nails. If you’re ready to quit, talk to your doctor about smoking-cessation programs. But if you continue to smoke, yellowness and changes in nail texture will likely keep getting worse. Your doctor may recommend you take certain medications, such as cholesterol medications to help with plaque build-up in your blood vessels, and blood thinners to improve your circulation.
5. Yellow nail syndrome
- Yellow nails
- Nail thickening
- Loss of your nails’ cuticles
- Loss of lunulas (the white half-dome shape at the base of the nails)
- Occasional splitting of the nail and swelling of the skin around the nail
- Respiratory problems, such as a chronic cough
- Lymphedema (swelling) in your lower legs
Yellow nail syndrome is a very rare condition that affects your nails and your respiratory and lymphatic systems. The disease may be inherited, but it often occurs randomly, usually in people over age 50. Yellow nail syndrome affects all of your nails.
The cause of yellow nail syndrome is unknown. In rare cases, it appears in people who have an autoimmune or lymphatic disease or cancer.
Treating yellow nail syndrome
There is no specific test for yellow nail syndrome, so your doctor will make the diagnosis based on your medical history and a physical exam. Changes to the nails are often permanent, but you may be able to improve their appearance by taking oral vitamin E supplements or applying a topical vitamin E solution to your nails.
Not every person with a yellow nail needs an antifungal treatment. If you are unsure if you have a toenail fungus, your doctor can send a small sample of your nail to a lab for testing. —Dr. Gimbel
Other medical conditions that may cause yellow toenails
- Psoriasis: A “salmon patch” that looks like a pink- or yellow-colored oil drop develops on the nail when psoriasis affects the nail bed.
- Sarcoidosis: Yellow discoloration of the nails, often with pitting, bleeding under the nails, hyperpigmentation of the nail bed, or inflammation of the skin around the nails.
- Diabetes: Yellowing, brittleness, and thickening of the nails due to decreased circulation.
- Thyroid disease: Yellow nails, plus overgrowth of the nails, lifting of the nail off the nail bed, nail clubbing, and swelling of the toes and fingers.
What deficiency causes yellow toenails?
Though you may have read that certain vitamin or mineral deficiencies can cause yellow nails, there is currently no evidence that this is true.
How do you prevent nail polish from causing yellow toenails?
Using darker shades of nail polish can often leave a yellowish stain on your nails. This is less likely to occur if you switch to lighter colors. But if you prefer dark nails, you can protect your nails from yellowing by applying a clear base coat before you put on polish.
Getting rid of yellow toenails
If your nails turned yellow due to a fungal infection, try this at-home treatment:
- Soak your nails in warm water for 5 to 10 minutes.
- Trim and file your nails (when necessary).
- Apply an over-the-counter anti-fungal solution or cream to your nails, such as clotrimazole or undecylenic acid. An alternative is to apply Vicks VapoRub to your nails, but this may be less effective than anti-fungal products. Other less-studied products that may help are tea tree oil, oregano oil, sunflower oil, snakeroot oil, and baking soda.
- Repeat this process daily until your nails have returned to normal.
Keep in mind that these treatments may take weeks or even months to show noticeable improvements (if they work at all). If you don’t notice any changes after a month of treatment or your symptoms are getting worse, see your doctor. You may need prescription medication.
Should you see a doctor?
See your doctor or a podiatrist in the following situations:
- You’ve tried at-home treatments for a month and your nails aren’t improving.
- You have pain in or around the nails.
- You have fevers or drainage or redness around the nails.
- You have medical conditions such as diabetes, psoriasis, thyroid disease, and lung problems.
- You’re a smoker.
- You notice new swelling of your lymph nodes.