Learn more about diagnosis, treatment, and prevention
There are more serious causes behind this condition and, as you will read, covering up your feet may actually harm you more than help you.

Sometimes, toenails naturally thicken as people get older. Combined with diminished blood supply, your nails can grow more slowly, thicken, and become increasingly susceptible to infection. While thick yellow toenails look awful, you shouldn’t just view this condition by how your toenails look. That’s because another culprit behind this condition is often fungi—and the laws of how fungi normally grow can also apply to your toenails.
You might remember from Biology 101 that fungi like warm, dark, and moist places to grow. That includes places such as your shoes, socks, and stockings. When you wear your shoes or socks all day, leave them in damp, dank places, or expose them to moist conditions (like high humidity or rain), fungi are more prone to grow.
As you know, it’s easy to crack a toenail when running, playing tennis, or simply just banging or stubbing your toe. A toenail crack gives fungi an opening and a place to live. Once inside your toenail, it’s extremely hard to get rid of a fungus. That’s because your toenail—almost like a Band-Aid or cast—keeps the fungus in place. With nowhere for the fungus to escape or get naturally cleaned out, it stays…and grows.
You increase the likelihood of acquiring a nail fungus by frequenting health clubs, using community showers, or sharing emery boards.
If your toenails show any of these symptoms, you may have thick yellow toenails caused by a fungus. Read about treatment and prevention tips from the experts at FootSmart
Sometimes, thick yellow toenails indicate that you may have a hard-to-diagnose foot condition. In some cases, your podiatrist might take a biopsy of the alleged fungus and have it analyzed by a pathologist. The pathologist will first check to make sure you are not suffering from psoriasis, eczema, dermatitis, or another kind of skin condition. To confirm the diagnosis of a fungal infection, you may take a KOH (potassium hydroxide) test and Periodic acid-Schiff (PAS) test. These are accurate, scientific chemical tests that ensure a proper diagnosis of your specific fungal infection.
While thick, yellow toenails might be hard to treat, there are some important ways to fight off and prevent this condition.
If you’re already diagnosed with thick yellow toenails, currently fighting off a nail fungus, or prone to a reoccurrence of nail fungus, YOU CAN TREAT THIS CONDITION BY DOING THE FOLLOWING:
If the fungus or thick yellow toenails persist despite your own treatment attempts, we recommend that you see a podiatrist for additional treatment. Your podiatrist may run some tests, more accurately diagnose your condition, and prescribe a stronger medication to fight off the fungus. Since there are 17 different organisms that can cause nail fungus, your podiatrist can work with you to find the right customized treatment.
