Ok…we all know that to stop the spread of the corona virus we need to be diligently washing our hands.  But do you know the science behind hand washing and why it is so important to wash for a full 20 seconds?

There are actual scientific reasons for all those hand washing tips that we have been inundated with and it isn’t simply to wash away the germs from your hands. The lathering, scrubbing and rinsing actually keeps the virus from infecting a human cell.

Hand washing physically dismantles and destroys the virus.

As with most viruses, the corona virus or COVID 19, is encapsulated by a lipid membrane, a coating of fat. This lipid membrane protects the virus from our immune system as it invades and infects our bodies.   

The act of washing your hands does 2 things:

  • First, the friction caused by rubbing our hands together helps to weaken and breakdown the protective lipid membrane of the virus.
  • Second, the soap molecules also act on the lipid layer to break it down and disrupt it. Whether scented, anti-bacterial or natural, soap is a mixture of fat, water and an alkali, or basic salt. The fat in the soap bonds with the lipid membrane of the virus and breaks it open.  Once the protective membrane of the virus is penetrated, the content of the virus is released, deactivated and washed away. Leaving it unable to bind and enter human cells.   
Think about what is needed to wash a greasy pan.  Will rinsing in water alone breakdown and remove the grease?  No you need soap.  The soap breaks down and neutralizes the fats in the grease so it can be easily washed away.  When viruses interact with soap, the same thing happens.   

How much time does it take for soap to breakdown the lipid membrane? 20 seconds! Hence the advice for washing your hands for 20 seconds. 

Are anti-bacterial soaps more affective?  No.  According to the FDA, there is no evidence that antibacterial soaps are any better at killing viruses than plain soap and water. In fact, in 2016, the FDA banned 19 antibacterial additives commonly found in antibacterial soaps that potential harmful to humans and the environment. There is also concern that the use of antibacterial soaps may increase the risk of generating drug-resistant bacteria. 

What about hand sanitizers? Alcohol based hand sanitizers can also break down the lipid membrane of a virus through a chemical reaction. The hand sanitizer needs to be at least 60 percent alcohol content to be effective. However, unlike the rinsing action that occurs with hand washing, hand sanitizers don’t wash the content of the virus from our skins.

So if you have access to soap and water, choose that method first.

Bringing your hand washing technique up to speed:

  1. Temperature of the water doesn’t matter. You can remove the virus using any temperature water.

  2. Choose liquid soap over foam or bar soap.  Liquid soap works better at washing away bacteria than foam soaps. Because liquid soaps are thicker than foam soaps, you tend to wash your hands for a longer period of time to wash and rinse the residue from your hands. 
    Bar soaps can also be used but when they sit around wet and slimy, they can start to harbor bacteria, and the more the soap is used, the more microorganisms it holds.  If you are using bar soaps, rinse them off prior to using and store in a place that will allow it to dry off. 
  3. Dry your hands completely.  Further rubbing your hands with a towel will remove any remaining germs left behind after washing.  Wet hands are more likely to spread germs than dry hands.  
  4. If using a hand sanitizer, let it fully dry on your hands.  If you pat dry your hands before the sanitizer has fully dried, you risk reducing its effectiveness.

I hope you are staying healthy, fit and sane during these days of confinement. 

I would love your feedback as to what you are doing to reduce the stress of being quarantined. 


Susan Brady
is a Physical Therapist,
Nutrition Consultant and
Doctor of Integrative Medicine.
She has been treating women with osteoporosis for over 30 years and is dedicated to helping people achieve
lasting good health and vitality.

Want to learn more about how you can improve your bone health? Contact me for a free 15 minute phone consult to learn more about the BONES Method™ and how it can help you achieve strong, healthy bones for life!

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