Toenail fungus is an infection and it usually starts off as a spot or discoloring of the toenail. It is typically not painful and therefore people tend to ignore it. If it goes untreated the infection goes deeper and spreads. The toenail can go from having a small discolored (yellowish) spot to a full blackening of the toenail. The toenail also can become thick and start cracking.
Toenail fungus can be caused by a yeast infection and molds. When the infection or mold gets between the toenail and the skin it causes the discoloration. Fungus can also affect fingernails but it is most common in toenails.
The most common risk of toenail fungus increases when you walk barefoot in damp public areas such as swimming pools and gym shower rooms or your feet sweat a lot in your shoes. However, there are many other situations which might increase your risk of contracting a nail fungus, including but not limited to receiving chemotherapy for cancer, diabetes, poor circulation, and psoriasis.
The best defense against toenail or fingernail fungus is a strong immune system. There are both topical creams and medicines as well as internal supplements and medicines to help keep your nails free of fungus.
Resources:
American Academy of Dermatology Association, Nail Fungus: Who Gets & Causes
https://www.aad.org/public/diseases/a-z/nail-fungus-causes
Last viewed: 20240701
Foot & Ankle Medicine, What do your toenails say about your health?, Steven Edwards, March 9, 2023
https://stevenedwards.com.au/what-do-your-toenails-say-about-your-health/
Last viewed: 20240702
Mayo Clinic, Diseases & Conditions, Mayo Clinic Staff, May 15, 2024
https://www.mayoclinic.org/diseases-conditions/nail-fungus/symptoms-causes/syc-20353294
Last viewed: 2024070