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Everything You Need to Know About Black Toenails


    Everything You Need to Know About Black Toenails


    Runners often face different issues, especially those that are related to feet, like blisters, callouses, pain, and even fractures. Another issue that can occur in runners is a black toenail. It sounds surprising, but it’s actually common. If you run regularly, you can pretty much expect a black toenail or two at some point in time.

    When you get a black toe, it usually indicates you’ve moved your training to a higher level. This is due to the fact that black toenails in runners often occur as the level of intensity increases. Those who run a mile or two at a time a couple of days a week are less prone to black toenails than people who run multiple days of the week.

    In most cases, black toenails caused by running are not a reason for concern, hey can be annoying and unsightly. Here’s what you need to know about black toenails:

    Running and black toenails.

    The repeated trauma caused by the mechanics of running is the most common reason for black toenails in runners. During running, your toes are hitting somewhere in your shoes. This pressure is pushing on the toenail plate itself leading to bruising or bleeding underneath the toenail. This phenomenon is called a subungual hematoma which actually means a simple bruise under the nail.

    You might experience a black toenail after your run. You may first notice a small black spot, however over the next few days, the discoloration can increase. The drying of the blood can cause your nail plate to separate and loosen which means your toenail can fall off in weeks, or even months.

    What to do about black toenail?

    Actually, running-related black toenails don’t require any treatment and they will go away by themselves. If you feel annoying pain, you may use some medications. 

    In mild cases, discoloration will go away in six to nine months to grow out completely. If your black toenail is constantly hurting, it’s wise to visit a podiatrist. Your doctor can make a few tiny holes in the nail in order to drain some of the blood, decrease pressure, and alleviate pain. If your subungual hematoma is not aching, you can continue to run as usual.

    How to lower chances of getting the black toenail?

    While it’s not possible to completely prevent black toenails, especially if you’re running long or often, you still can do some things that can lower your chances of getting subungual hematoma. Always keep your toenails short. Your nail should be flush with the end of your toe. The less the nail extends the fewer chances of a hit during running.

    The wrong shoes can increase the risk for repetitive trauma. Make sure that your running shoes give you about a half-inch of room from where your longest toe ends. Your socks are important as well. Thick socks can make shoes too tight leading to nail injury. 

    Other causes of black toenails.

    If you are sure your black nail is caused by running, you have nothing to worry about. However, there are some other causes that can make your nail turn black. 

    In rare cases, black toenail might be caused by a type of skin cancer called subungual melanoma. A study published in Dermatology reports that subungual melanoma occurs only in 3% cases of melanoma.

    Remember that subungual melanoma is the most concerning albeit the rarest reason for black toenail. In some cases, black toenails might occur because of a fungal infection. This cause is very likely if you walked barefoot one too many times in public places like pools or locker rooms. It’s also likely that black toenails can just be a natural pigment change as you get older.