How often should I replace my bath sponge?

bath sponges
Disinfecting and replacing your sponge regularly will ward off bacteria and mold.
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After a long day or a grueling workout, a hot bath might be your top priority. But before you start scrubbing, take a look at your bath sponge, and ask yourself how long it's been since you replaced it. If you can't remember, it's probably been too long. You might think you're just being frugal, but hanging on to a well-used bath sponge may mean that you've created a new home for bacteria and mold -- a home that touches your body on a daily basis.

Whether it's a synthetic mesh bath pouf, a loofah or something else, regularly changing out your used bath sponge for a new one can keep bacteria and mold at bay. In the warm, wet atmosphere that exists in most bathrooms, these organisms can grow quickly, and they could spread to your skin if you don't change your sponge regularly. This misuse of sponges can lead to rashes or infections due to bacteria, and using a sponge that hasn't been properly cleaned or stored can also promote the growth of mold in your home.


After using your sponge each day, you should wring it out to remove excess water and hang it in a well-ventilated area to dry. Remember that synthetic, or human-made, materials will dry faster than natural ones, like loofahs or sea sponges. Dermatologists recommend that you throw out a loofah after three to four weeks, since it easily grows bacteria in its crevices, and by that time will have lost some of its exfoliating properties. You should toss a mesh bath pouf, which is more resistant to bacteria, after eight weeks [sources: Crean, Fitness Magazine]. If you want to be extra cautious, you can also disinfect your bath sponge every few days.

The presence of bacteria is a fact of life, and it exists everywhere. Read on to learn how to minimize the risks to your health caused by the bacteria on your bath sponge.


Sponges and Bacteria

Bacteria live everywhere, from the surfaces in our homes to the insides of our bodies. Some bacteria are beneficial to human life; others cause harm. Leaving a moist sponge in the bathtub day in and day out gives some of the harmful germs a hospitable place to set up shop.

Loofahs are especially vulnerable to bacterial growth. These natural sponges have many nooks and crannies that -- especially when moist -- tend to invite bacteria. Additionally, dead skin cells commonly found on loofahs provide food for bacteria, giving them even more reason to move in. In fact, one study found that the amount of bacteria like P. aeruginosa, which causes a variety of infections, grew exponentially in 24 hours when exposed to a loofah sponge. The study's authors also found that soaking the sponge in a bleach solution on a regular basis killed off the bacteria, and thus helped to prevent infections [source: Bottone].


The same risks apply to other types of sponges, too. Even plastic mesh bath poufs can become infected with bacteria and lead to rashes on the skin. One such rash, called folliculitis, is an infection of the hair follicles. Mild cases of folliculitis often look like clusters of small, red bumps around hair follicles, and symptoms of folliculitis include itching and tenderness [source: Mayo Clinic]. Although such cases normally clear up with home treatment, if the area worsens or does not improve within three days, you should seek medical attention.

Bacteria aren't the only thing that can grow on your bath sponge; mold can also be a problem. Continue to the next page to learn more.


Sponges and Mold

Mold, a kind of fungus, thrives in wet, warm areas like bathrooms. If you don't regularly dry and disinfect your bath sponge, it could become a haven for mold and possibly help spread the fungus throughout your home.

Fungus reproduces with tiny particles called spores. These spores can be dangerous when people breathe them in. Mold spores trapped in your lungs can cause serious allergic reactions, and many people may have mild reactions to skin contact with the spores, such as redness and itching [source: Bode].


Once mold begins to grow in an area, it can spread easily to other locations [source: Consumer Reports]. Part of the natural outdoor environment, mold spores travel through the air and can begin growing indoors when they land in a moist area that will support them [source: U.S. Environmental Protection Agency]. To ensure that this location isn't the sponge with which you clean yourself, you need to follow some basic hygiene rules.

The same measures that prevent bacterial growth also will prevent mold from forming on your bath pouf, loofah or sponge. Rinse the sponge after each use, hang it to dry and disinfect it with bleach or another method on a regular basis. If you can see mold on your bath sponge, it may be best to get rid of it right away and buy a new one. Most sponges are inexpensive, and the few dollars that you'll spend are worth preventing the illness you might contract by using a contaminated item on your body.

To prevent mold and bacteria from growing, the best course of action is to clean your bath sponge regularly. Read the next page to learn how best to clean your sponge or loofah.


Cleaning Sponges

For maximum exfoliating power and minimum risk of mold and bacterial growth, you should replace a plastic mesh bath pouf after eight weeks and a natural sea sponge or loofah after three or four weeks. Disinfecting your bath sponge every day will also help reduce the amount of bacteria and mold that may be growing in it [source: Crean].

Keeping your bath sponge as dry as possible when not in use is one way to hold bacteria at bay. However, one study found that loofah sponges needed to air dry for at least two weeks to significantly lower the level of bacteria they contain [source: Bottone]. This means you need to take extra steps to ensure a germ-free sponge.


In addition to rinsing and hanging it in a well-ventilated area to dry, you can use a bleach solution to disinfect your bath sponge. To clean a synthetic sponge, you should soak it in three quarters of cup of bleach per gallon of warm water. For a natural sea sponge, use one-quarter cup of bleach per gallon of cool water. You should soak either type of sponge for at least five minutes [source: Columbia University]. An easier but possibly less effective approach entails throwing your sponge in the washing machine or the dishwasher. Laundry and dishwashing detergents are gentler and less toxic than bleach, but they may not kill all the bacteria and mold present.

By disinfecting your bath sponge each week and replacing it after several weeks, you can keep germs from taking root in your personal care items, bathroom and body. Read on for more information about keeping your skin clean and healthy.


Lots More Information

Related HowStuffWorks Articles

  • Bode, Marilyn. "Help Yourself to a Healthy Home." Federal Citizen Information Center. 2002. (Accessed 8/23/09)
  • Bottone, Edward J., Anthony A. Perez, II, and Jamel L. Oeser. "Loofah Sponges as Reservoirs and Vehicles in the Transmission of Potentially Pathogenic Bacterial Species to Human Skin." Journal of Clinical Microbiology. 32(2), February 1994: 469-472. (Accessed 9/2/09)
  • Columbia University. "Are Washcloths and Other Body Scrubbers Bacteria Factories?" Go Ask Alice! March 28, 2003. (Accessed 8/26/09)
  • Consumer Reports. "The Basic Facts About Bathrooms and Household Mold." November 2007. (Accessed 8/26/09)
  • Crean, Ellen. "If It's Old, Throw It Out." CBS News. August 8, 2003. (Accessed 9/2/09)
  • East Metro Public Health. "Personal Hygiene." 2008. (Accessed 9/2/09)
  • Fitness Magazine. "When to Toss It." (Accessed 8/25/09)
  • Mayo Clinic. "Folliculitis." October 5, 2007. (Accessed 8/26/09)
  • U.S. Environmental Protection Agency. "Mold Cleanup Guidelines." April 13, 2009. (Accessed 8/26/09)
  • Van Delden, Christian and Barbara H. Iglewski. "Cell-to-Cell Signaling and Pseudomonas Aeruginosa Infections." Emerging Infectious Diseases 4(4), October-December 1998. (Accessed 9/2/09)