Common causes of yellow toenails include excessive nail polish use and fungal infections. However, yellow toenails can sometimes be a sign of a more serious underlying health condition ...

If you have nail fungus, your toenail color might be: white yellow reddish brown green black ... When you apply nail polish to the surface of your nail, it can penetrate and stain deeper layers ...

There’s nothing in traditional nail polish that will directly harm your fingernails or toenails ... Thickened, crumbly, yellow or misshapen nails can signal a fungal infection, Dr. Rubin ...