Hand Sanitizers or Soap? Which is scientifically proven to work best?

Hand sanitizers or soap?  Which is scientifically proven to work best to keep us safer? Soap versus hand sanitizers has become more of an issue than ever!

Let’s look at the science behind soap. And look at the science behind hand sanitizers. We’ll see how each one works and whether or not they destroy viruses and bacteria. Then compare the two. We’ll find our answer. Go science. 

Soap or Hand Sanitizers? Which is scientifically proven superior?

I wouldn’t give up my opposable thumbs, but the downside is that our invaluable hands have plenty of nooks and crannies where bacteria and viruses can hide. 

Ask any crime scene specialist! Science is knowledge. (And can be used for or against you in a court of law.) Today, we’ll use the science to benefit us!

hand sanitizers or soap? Susan Berk Koch and Louie
Clean hand and skeptical Louie
Forensic Specialist
Analyzing collected samples from crime scene
Crime Lab
Forensic Specialist finding facts with science

WHAT ABOUT SURFACES?

Are they clean?

HM....

Don't assume any given surface is clean

THE SCIENCE OF VIRUSES

When we cough, or especially when we sneeze, tiny droplets from our airways can fly! (gross) And at the time of this post, the controversy over airborne transmission of COVID-19 rages. (It is currently thought that coronavirus transmits via larger droplet transmission. Larger droplets fall quickly, onto surfaces within six feet.) 

Droplets from sneezing
Sneezing!

But let’s go back to virus science so we can scientifically prove if soap or hand sanitizer wins.

These droplets end up on surfaces. They dry out quickly. But the viruses remain active.  (Viruses are technically not alive. We won’t go into the why today.)

Human skin is an ideal surface for a virus.

The proteins and fatty acids in the membranes of our dead skin cells interact with the virus.

hand sanitizers or soap? Susan Berk Koch and Louie
My hand doesn't look quite as clean now, does it??

When you touch a surface with a virus particle, it will stick to your skin and get transferred on to your hands.

HERE’S THE BAD PART:

If you then touch your face, especially your eyes, nostrils, or mouth, you can infect yourself.

And it turns out that most people touch their face once every two to five minutes. Almost half of face touches involve mouth, nose, and eyes. Those are direct pathways for bacteria and viruses to enter our bodies.

Try your best not to touch your face! Not to bite your nails or cuticles. Pick your nose. Just…DON’T!

VIRUS CELL MEMBRANES = THE WEAK LINK

Coronavirus
Coronavirus

Coronaviruses are like many viruses. They have a protected outer surface made of a lipid (fatty) bilayer.

For our purposes, this means they have a head region that is attracted to water (hydrophilic), and a tail region that is repulsed by water. (hydrophobic)

 

In a water environment (aka you and me), the outer coating forms with the heads out. This helps the virus break through our cell membranes and hijack our cells. (UGH)

phospholipid_bilayer

BUT…this lipid bilayer is also the virus’ weakest link!

THE SCIENCE OF SOAP!

Enter our superhero…soap!

Our superhero, soap comes to the rescue.  Soap contains fat-like substances known as amphiphiles. They are similar to the lipids in the virus membrane.

The soap molecules compete with the lipids. They break up the regularity of the virus membrane.

Amphiphiles in soap
Amphiphiles in soap

The soap not only loosens the “glue” between the virus and our skin but also the  interactions that hold the proteins, lipids, and genetic material in the virus together.

Soap dissolves the fat membrane of the virus – and the virus falls apart! HUZZAH!

Amphiphiles head hydrophilic
Amphiphiles Circling

But soap doesn’t stop there!

Soap forms particles of their own that surround the virus parts. Apply water, and you’ll wash that bubble with the nasty virus down the drain!

The  bubble of soap that circles the broken pieces of virus is called a micelle.

Science of soap Smashing the virus cell wall
Science of Soap : Attacking the Virus Cell Membrane
Amphiphiles surrounding lipid of virus
Micelle
Soap Micelle encircling Virus DNA
Micelle circling virus material

IT TAKES 20 SECONDS

20 seconds of hand washing is needed to get all those nooks and crannies on your hands. Scientifically proven!

HAVE YOUR KIDS SING THE HAPPY BIRTHDAY SONG

Or hum it to yourself. It takes about twenty seconds!

In addition, the rubbing motion while washing with soap and water removes some of the dirty surface skin cells. Who needs those guys, anyway? 

But we can’t carry around sinks with running water!

 

Enter…hand sanitizers!

Faucet with running water
Running water

THE SCIENCE OF HAND SANITIZERS

Hand Sanitizers = Hero?

Let’s look at the science.

Science of hand sanitizers
What is in this bottle?

Sure, we can read the label of the bottle below but we need to know how to interpret it…which you’ll be able to do because you’re learning about the science of hand sanitizers here! 

Science of Hand Sanitizers
Read the label!

Have you seen a movie or show when someone gets shot? In westerns or survival movies, the characters sometimes pour alcohol on the wound. The victim winces. The hero takes a swig before expertly beginning his or her patch job.

We laugh or roll our eyes. Or think it’s a good idea, pause the show, and make ourselves a Cosmo.

There is something to be said for that! (The cosmos…pouring alcohol on a wound can cause tissue damage)

Making a cosmopolitan
Cosmopolitans

Alcohols perturb the structural arrangement of the membrane lipids. The cell membrane collapses. Scientifically proven!

Alcohol also denatures or disrupts the virus proteins. Viruses have that spikey part, used to penetrate our cells. That is made up of protein.

Corona virus protein spikes
Spiked protrusions are EVIL proteins

As the virus breaks down from the alcohol attack, its parts aren’t surrounded in a bubble of soap molecules. (micelle) They crumble.  Think of it like taking the nails (or those protein spikes) out of a picture frame. The frame would fall apart.

Do alcohol-based hand rubs destroy the COVID-19 coronavirus?

YES....

Scientifically proven! But there's a catch...

Okay, there are a few addendums for hand sanitizers to achieve hero status.

The CDC recommends at least 60% alcohol by volume to effectively knock those viruses on their microscopic butts.

Interestingly, the FDA recently increased their recommendation to not less than 94.9 alcohol by volume.

It takes about 30 seconds of rubbing to achieve benefits.

This way you can be more certain that  those virus  bonds are breaking. (No water to wash it all away…)

Non-alcohol antiseptics rely on benzlkonium chloride instead of alcohol. Don’t be fooled.

Be sure to read the labels! 

Don’t purchase anything unless it has at least 60% ethanol or isopropyl alcohol. Not even if it’s on sale.

HAND SANITIZERS OR SOAP? WHICH IS SCIENTIFICALLY PROVEN TO WORK BEST?

In our side-by-side comparison, here are two drawbacks of hand sanitizers….

WILL HAND SANITIZERS EFFECTIVELY RID DIRTY HANDS OF VIRUSES OR BACTERIA?

Sadly, NO

Hand Sanitizers do not eliminate dirt

HERE'S ANOTHER CONSIDERATION

Which costs less; soap or hand sanitizers?

SOAP!

Okay, this is not a science fact, but it's nevertheless true.

Good rule of thumb:

 If your hands are dirty, such as before and after eating, using a restroom, playing sports or engaging in any outdoor activities, hand sanitizer won’t be effective.

 

The sanitizer won’t eliminate the dirt, where the viruses could be hanging out. 

We aren’t rubbing hard either, so no surface skin cells are eliminated.

SOAP OR HAND SANITIZERS? FINAL VERDICT

Hand sanitizers DO offer solid protection when you’re out and about, provided you follow the guidelines!

Which is the best? Science tells us :

SOAP WINS!

Super Heroes times 3
SUPERHEROES

The moment I walk in the door, I  wash my hands thoroughly with soap and water. I want you to do this, too!

No, I never sang the happy birthday song before researching this post, but I will from now on. I hope you do as well!

Chocolate Cake
Chocolate cake! Clean hands! Let's do this.

Let’s wash our hands and have a delicious bite to eat!

 

Which of the three treats would you choose?

 

Chocolate cake, appetizers, or gelato?

Cocktail sand appetizers Susan Berk Koch
Appetizers and ginger beer!
Gelato
Or maybe some gelato!

DON'T MISS OUT ON THE SCIENCE MAGIC

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78 thoughts on “Hand Sanitizers or Soap? Which is scientifically proven to work best?”

  1. Perfectly times article, Sue. Love this and have wondered and argued with people. I have always maintained that washing your hands with soap is better, Now I have this article to prove it. Thank you,
    Eva

    Reply
  2. Informative and fun post! I carry hand sanitizer with me so that I can disinfect my hands or surfaces when I have to go out. Once I get home, I do lather up with soap and water! Excellent point that soap and water costs much less, too.

    Reply
  3. Thank you so much for breaking down the science of this complicated subject! This was so informative and entertaining to read! Thanks for sharing! 🙂

    melissakacar.blogspot.com

    Reply
  4. I used to wonder why I was always getting colds/viruses, then I realised I touch my face almost every 5 minutes, if not more often. I don’t know why, it’s just something I do….trying not to do during this pandemic whilst I’m out and about has been fun and games 🤦‍♂️😂

    Reply
  5. This is such a great and informative post. I learned so much from reading it. Thanks for sharing this. Especially given the circumstances of everything that’s going on right now!

    Reply
  6. Yay for soap! What about “soap nuts”? I bought some at Trader Joe’s and am using them in the laundry. They work great, and there’s no plastic involved. But I wonder if they do the same thing as soap. I won’t be using them on my hands, but I wonder how they work.

    Reply
    • Here’s what I found. “Soap berries, also commonly called soap nuts, are the berry-like fruit (related to the lychee fruit) that grows on the Sapindus Mukorrosi tree, native to India and the Himalayas. These berries produce a soap called saponin, which operates as a natural surfactant.”

      They sound cool! Thanks for mentioning them!

      Reply
  7. I have been wondering about this! Glad you posted it. I use hand sanitizer when I am out, but I need to be better about rubbing for 30 seconds…yikes

    Reply
  8. This is such an interesting post. I had always wondered if soap would be enough and now I know. In the past I’ve been guilty of touching my face and leaning on my hand. Since Covid started, I’ve made a conscious effort to not do this and the difference in my skin is noticeable. I dread to think what bacteria I was passing onto my skin.

    Reply
  9. Great post! I think soap is always the best options, but of course if there’s no soap, hand sanitzer works. Either way, whenever I go out to the groceries and such, I carry a hand sanitizer. But I still feel a bit germophobic and have to wash my hands as soon as I get home. I have a bad habit of touching my face, so this has been a good habit breaker for me.

    Grislean | gemlesschosen.com

    Reply
  10. Thank you for this great breakdown and reminder about the importance of washing hands. We’ve been washing our hands a lot more since the pandemic started (like everyone else!) but have started getting lazy and just use hand sanitizer when we’re in a rush. But will make more time to wash with soap!

    Reply
  11. I knew soap was better, and the 20 seconds thing, but I guess the issue there is more about how well you’re washing your hands. I always use soap at home but keep sanitiser in my bag when I’m on the go x

    Sophie

    Reply
  12. We always have soap at home and wash our hands whenever we come in (as well as other times!) but as you say, it’s not practical out and about. Good to know that a combination of the two will work effectively though – great post! Lisa

    Reply
  13. This is such a useful post Sue! Definitely highlights the benefits of using both, and keeping our hands clean, something that is so important at the moment. I also didn’t realise how often I touch my face, until I consciously tried to stop!

    Thanks for sharing!

    Aimsy xoxo
    Aimsy’s Antics

    Reply
  14. I love using sanitiser and we always have soap around the house. This is a really eye opening article, so thank you for sharing!

    Em x

    Reply
  15. Great post! Thank you a lot! This topic is very important and it’s nice not only to hear the answer but also understand the thing!!!

    Reply

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Susan Berk Koch
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