Why Do Your Toenails Turn Black (and How to Fix It)
Black toenails are common among marathon runners and other serious runners, but they don’t have to be tolerated. The problem is likely made worse by the fit of your shoes, so here’s a guide on how to avoid black toenails in the first place and how to deal with them when they occur.
And yes, in case you were wondering: black nails can sometimes fall off. If this has never happened to you, then you are probably completely disgusted right now. If that’s the case – and I’ve been there – you know it’s really not that big of a deal and they grow back. But more on that in a second.
Why do toenails turn black?
Typically, a black (blue or purple) toenail is just a bruise that can be seen because the toenail is clean. This is exactly what we will talk about today. These bruises can happen suddenly—like if you drop a plate on your toe—or they can happen when you bump your toes into the front of your shoes thousands of times every mile.
There are other reasons why a toenail may change color, so if you have any doubts about whether you have a bruise or something more serious, ask your doctor to examine it. These other causes may include normal pigmentation changes that can occur over time, various types of toenail fungus, and even some types of skin cancer. For example, discoloration that extends beyond the nail is a cause for concern; the same can be said for black spots that stay in place for months rather than growing or going away. But usually, if you’ve increased your mileage and your toes have started to turn black, the reason is obvious.
Choose your shoe size
Although bruised toenails are common in people who run a lot, they are by no means inevitable. If you keep getting bruised toenails, your shoes may be too tight to the toe.
I got my first black toenails when I started training for a marathon, after years of never running more than three to five miles at a time. I bought size 8 running shoes to fit my size 8 feet and they were fine all these years until I increased my mileage. So when it came time to buy a new pair, I upgraded to the 8.5. My toenails stopped turning black and as a bonus, I also stopped getting blisters.
Your feet will swell a little when you run, so it’s wise to buy shoes with this in mind. You might think this would make your feet slide better in the sneakers, but the sneakers are made so that you can lace them tightly around the instep and still leave plenty of room around your toes. If you need extra help keeping your foot closer to the back of the shoe, use an extra pair of lace holes and tie the heel clamp to fine-tune the fit.
Change your socks
If you run in thick socks, switching to thinner ones will help you free up some space. As a bonus , thin socks made specifically for running will often make your feet less prone to blisters. Try Feetures or Swiftwick .
Trim your nails
Another way to prevent nails from getting into the front of your shoes is to keep them trimmed. Cut them as short as you’re comfortable with ( too short can also be annoying), and trim or file them often to keep them that way.
Draw them maybe
Over the summer I had black toenails and started buying nail polish in interesting colors. The bruises will show through any sheer fabric, but it was fun to experiment with dark colors including blue and purple.
I couldn’t find expert consensus on whether painting bruised toenails is harmful. It’s not true that nails need to “breathe” (the tissue in our toes gets oxygen from our blood rather than directly from the air), but in some cases, nail polish and the chemicals we use to remove it can contribute to drying out nails. or they may simply make it difficult to check whether the nail underneath is healthy.
I will say that many runners paint their nails without any side effects, but if you have any doubts, you might as well save your nail polish for special occasions. The dark color of the bruise will fade over time.
Seek help if they hurt
Blood pooling under a bruised toenail can cause so much pressure that it can cause pain. A doctor or other health care provider may prick the nail to drain fluid and relieve pressure.
There is no shortage of instructions online on how to do it yourself, using a hot needle, a paper clip, or even a drill. Although people do it, I do not recommend doing the surgery yourself. In any case, toenail drainage is performed in cases where the pressure of the fluid under the nail causes pain. It will not help toenails that are painless or slightly sore after turning black from mild bruising.
We are waiting for them to disappear
This is the most interesting and unpleasant part: damaged toenails sometimes fall off. Sometimes they turn black and then fall off, but you can also have your nails fall off without a visible bruise, or vice versa.
This is less unpleasant than it seems because the new nail begins to grow under the old one. You may not even notice what’s happening until the new nail is almost in place. One day you just go to trim your nails and notice that one of them lifts up easily – it’s the old, top nail, ready to come out.
This transition period can be awkward, and you have two options. First, if the nail is still mostly attached, cover the nail with adhesive tape or athletic tape, making sure that the free edges do not catch on the toe box or the inside of the shoe. Since the fresh new nail underneath is thin and may not yet cover the entire nail bed, preserving the old nail will help protect the finger.
Another option is to remove the old nail, which you can do as soon as you feel it is a better option than covering it with tape. Consider doing the job carefully with a nail trimmer (instead of shaking and hoping for the best), and then use a file to smooth out any rough edges.