The Supercool Reason Soap Is Better Than Hand Sanitizer

The Supercool Reason Soap Is Better Than Hand Sanitizer

There’s amazing science in those suds

washing hands

One of the best weapons in the fight against COVID-19: The humble bar—or bottle—of soap. It may be old school, but it’s super-powerful. It has nifty molecules that send the virus (and other nasty stuff) right  down the drain. 

“Ordinary soap is highly effective at reducing exposures to harmful or pathogenic microbes,” says environmental epidemiologist Irva Hertz-Picciotto, Ph.D., M.P.H., director of the National Institutes of Health–funded Environmental Health Sciences Center at the University of California, Davis.

Coming in a close second to soap is hand sanitizer containing at least 60 percent alcohol. A squirt of sanitizer can knock out the harmful coronavirus germs, too. And though it may leave virus residue on your hands, it’s good to have for those times when you don’t have access to soap and water.

Antibacterial products, including hand sanitizers, are good at doing what they promise to do—killing up to 99 percent of bacteria. But there’s one important caveat: They get rid of good bacteria along with the bad stuff.

“Most people believe that all bacteria are bad, period, and that the goal is to eliminate or minimize all exposures,” Hertz-Picciotto says. “This is complete folly, because we live in a totally symbiotic relationship with huge numbers of bacteria that enable us to function.” Good bacteria can help with things like digestion and nutrient absorption, she says.

On the other hand, regular soap is selective about the kinds of bacteria it washes away: It removes the bad stuff but leaves the good bacteria unharmed.

Hand sanitizers are a critical tool for doctors, nurses, emergency workers, and other medical personnel, according to the Centers for Disease Control and Prevention (CDC). Plus, they’re great for the rest of us when we don’t have easy access to soap and water. Remember to choose one that’s at least 60 percent alcohol, use a generous squirt, and rub the gel all over the surfaces of your hands until they’re dry.

So let soap be your go-to for clean hands. Here’s a look at exactly why it’s is so powerful—and how to get the most out of it.

The Amazing Science of Soap
Soap molecules have two ends: one that attaches to the coronavirus, which has a lipid membrane (a fatty outer shell), and one H20-loving end that water attaches to.

So when you wash your hands, the soap latches onto the virus, the water grabs ahold of the suds, and both are washed down the sink. Cool, right?

Keep in mind that for all of this to work, you need to spend at least 20 seconds washing, according the CDC. Scrubbing is key, because it creates enough friction to lift the germs off of your skin and out from under your nails.


The information in this story is accurate as of press time and posting. To limit the spread of the coronavirus, it’s important to continue practicing social distancing (keeping at least 6 feet away from people outside your household) and washing your hands frequently. You should also be appropriately masked per CDC guidelines. Because the situation surrounding COVID-19 continues to evolve, we encourage readers to follow the news and recommendations for their own communities by using the resources from the CDCWHO, and their local public health department.