You may have a nail fungal infection — also called onychomycosis (on-i-ko-mi-KO-sis) — if one or more of your nails are:
* Brittle, crumbly or ragged
* Distorted in shape
* Dull, with no luster or shineA dark color, caused by debris building up under your nail. Infected nails may also separate from the nail bed, a condition called onycholysis. You may even feel pain in your toes or fingertips and detect a slightly foul odor.
Nail fungus is more common among older adults for several reasons, including diminished blood circulation, more years of exposure to fungi and because nails may grow more slowly and thicken with aging, making them more susceptible to infection. Nail fungus also tends to affect men more than women and those with a family history of this infection. Resistance to fungal infection likely has a genetic component.
These factors also can increase your risk of developing nail fungus: