Does soap kill germs?
Originally Published: May 4, 2001 - Last Updated / Reviewed On: July 3, 2015
I remember reading somewhere a couple years ago that hand or bath soap does not KILL germs or sterilize our hands. Rather, it helps loosen dirt and grime, and it makes the skin more slippery so that dirt and germs rinse off more easily with water. It makes sense to me, but my daughter who is studying for a medical career said I was off my rocker. I am getting older, but I'm sure I didn't fall out of my chair onto my head — but instead read that in a health newsletter somewhere. What's the skinny? Can my daughter trust me and what I read (in this case, at least), or should I throw in the towel (for 100 percent memory recall)?
— Slippery Soap
Dear Slippery Soap,
You deserve a high five for asking about a crucial illness-fighting habit. To answer your question, you’re correct about how the average hand soap works, but you and your daughter may have been talking about two slightly different versions of the sudsy stuff. Regular household soap and antimicrobial/antibacterial soap work in different ways to get your hands squeaky clean. The appropriate use of either one may depend on where you’ll be washing your hands (and what you’ll be doing with them once they’re clean). And, when it comes to liquid versus bar soap, there is a preferred choice to further avoid germs when you lather up your phalanges (more on that in a bit).
Regular household soap or cleanser does not kill germs (as you correctly asserted) — rather, it suspends (or lifts) them off the skin surface, allowing the microbes and soil bits to be rinsed down the drain. This property of soap explains why it’s more effective to use soap when washing hands, rather than just relying exclusively on warm water. Additionally, people tend to scrub their hands more thoroughly when using soap, which further removes germs.
Antimicrobial or antibacterial soap, on the other hand (pun intended!), does kill bacteria and other microorganisms, and can sometimes inhibit their future growth. This is likely what your daughter will use before she performs patient exams. Antibacterial soap is available for home use, but some experts worry that using antimicrobial products may create stronger, more resistant strains of bacteria. Additionally, there is no evidence to suggest that antibacterial soaps are more effective than plain soap for preventing infection under most circumstances in the home or in public spaces. Therefore, when it comes to lowering the risk for spreading infection, the Centers for Disease Control and Prevention (CDC) suggest that regular soap is adequate for the general public, and that antibacterial soaps can be saved for those working in healthcare, child care, or food preparation settings.
Another worthy distinction to make when it comes to getting sudsy relates to the form of soap you use. Bar soap, unfortunately, can harbor germs and enable the spread of germs between individuals. Liquid hand soap is both easy to use and resists the spread of germs from one individual to another. It also often contains moisturizing agents that keep your skin from becoming dry, even after frequent washes.
Regardless of the type of soap used, proper and adequate hand washing is key to hand hygiene and is considered the best way to prevent the transmission of microorganisms. For more dirt on getting your digits clean check out Handwashing do's and don'ts.