 Wash your bath towel every use once a week or whenever it starts to smell. You should actually be washing it every three uses, about twice a week if you shower every day. Nearly 90% of bathroom towels are contaminated with bacteria that's found in feces. Reusing a towel too many times can irritate your skin, cause acne, and spread infections. The longer a towel stays damp, the longer yeast, bacteria, molds, and viruses are able to thrive on it. To keep your towel clean between washes, make sure to hang it up and let it fully dry after each use.