Toenail Discoloration: The Colors and What They Mean

Summer has ended and that means you’re probably putting away your favorite sandals until next season. However, keeping a close eye on your toenail color to make sure everything is crystal clear is very important throughout the whole year. Sometimes, toenail discoloration could be a sign of a medical condition that you would not otherwise be aware of if it wasn’t the sudden change in your toenail color. 

Here are 5 common abnormal toenail colors and what they can mean for your health.


Black toenails are usually a sign of trauma caused by direct impact, such as when something heavy falls on the toenail. Sometimes black toenail can signify a more concerning issue such as a fungal infection, or in even rarer cases, skin cancer such as malignant melanoma. So, if your black toenail keeps reappearing and you haven’t stubbed your toe or been skiing or exercising in tight shoes too long, chances are the dark toenail is medically related. 


Toenails that are white all over can be a sign of a fungal infection called superficial onychomycosis. This infection commonly spreads to the entire toenail, starting its way from the nail plate on the outside and working its way deeper into the toenail over time. While rarely a sign of a more serious medical problem, this infection can cause the toenail to weaken and crumble slowly or peel in thin layers.  


Bluish toenails that discolor the whole toenail are rare, but if you notice a blue speck or spot under your toenail, this is most likely a mole. Usually the mole, also called a cellular blue nevus, is harmless – but in extremely rare cases, it can turn into a malignant blue nevus, an extremely rare but serious type of cancer. If you notice this on your toenail, it’s best to get it looked at as soon as possible to rule out anything your doctor might find concerning.


Yellow toenails typically signify a fungal infection. Depending on how yellow the toenail is, and how long it lasts, this common issue usually does not require medical attention. In most cases, the yellow color resolves on its own and over-the-counter antifungal creams can help. But, if this is a consistent issue that doesn’t get resolved over time on its own or after using cream, it may be time to pay your doctor a visit. There could be an underlying issue such as diabetes or a thyroid disorder if the yellowish toenails worsen or if the nail changes in thickness or shape. 


Like yellow toenails, green could be a sign of infection as well. Not as common as yellowing toenails, greenish nails are typically caused by bacteria. Been to the public pool lately or walked barefoot around the health club? If yes, chances bacteria are to blame. Since this discoloration is not as common as yellowing toenails, if the color doesn’t resolve on its own in a few days or weeks, check in with your doctor for solutions on how to get rid of the bacteria. 

As always, we cannot stress enough the importance of visiting your podiatrist and getting a foot exam when something doesn’t seem to be quite right. Our toenails are a deeper reflection of what’s going on inside of our bodies. Paying attention to the color of your nails is important to make sure your health is in check and that all is good.

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