Showering may be bad for your health, say US scientists, who have shown that dirty shower heads can deliver a face full of harmful bacteria.
Tests revealed nearly a third of devices harbour significant levels of a bug that causes lung disease.
Levels of Mycobacterium avium were 100 times higher than those found in typical household water supplies, BBC News reports.
"If you are immune compromised or are susceptible to pulmonary infections, take a bath instead of a shower," says lead researcher Leah M. Feazel, of the University of Colorado, in Boulder. "If you are healthy and your immune system is functioning properly, you should not worry about the germs in your showerhead."
Mycobacterium avium, found in 20 percent of study samples, can cause lung infections in both healthy people and those with weakened immune systems, particularly smokers, alcoholics, people with chronic lung disease, and others with conditions that make it difficult to fight off infection. Symptoms include fatigue, a chronic dry cough, and shortness of breath, CNN informs.
"This really shouldn't concern average, healthy people. The main concern is for people who are immune-compromised," researcher Leah Feazel told Reuters Health. The findings, published in Proceedings of the National Academy of Sciences on Monday, are based on tests of about 50 showerheads taken from nine U.S. cities, including New York, Denver and Chicago.
The researchers said showerheads are not the only potential bacterial dispersants in the home, however.
Feazel said more research is needed to measure bacteria levels in household devices like humidifiers and evaporative coolers, reports Reuters.