In the era of COVID-19, two products that have seen exponential growth in usage are soap and hand sanitizer. One would hope that people were washing their hands often before COVID-19, but in 2020 keeping your hands clean has become one of the most crucial parts of our everyday routine. When it comes to killing those germs and viruses, especially COVID-19, two methods have become the preferred choice for hand cleanliness; using hand sanitizer or washing your hands with soap. So which way should you use when presented with both options? Let’s examine both products.
Washing your hands with soap has been the cornerstone of hand hygiene for thousands of years. However, when I refer to hand washing here, it means thoroughly washing your hands for at least 20 seconds as recommended by the CDC. Regardless of which method is the most effective, quickly washing your hands for 2 seconds while barely applying any soap does not count as washing your hands. The germs did not go away, and you’ve given yourself the false sense of security that you washed your hands.
So given that we correctly followed the appropriate steps to washing our hands, what did the soap and water do?
The science behind washing your hands is fascinating. Not only does it kill the germs, but it effectively cleans the grime that you’ve collected on your hands. When you wash your hands with only water, the massive oil and fat molecules can’t bind with water, which is why it’s so difficult to get oil off with just water. The answer to this problem is soap as it is made up of molecules that have two sides to it. One side is hydrophobic, which is a fancy word for something that doesn’t bind with water. This side of the soap molecule binds to oil, dirt, and even viruses; it then traps it in the soap molecule. This works in tandem with the hydrophilic side of the soap that interacts very well with water. So what ends up happening is that soap traps the oil and dirt during the 20 seconds you are scrubbing your hands and can be easily washed away because soap has two sides to it! Amazing! Fun fact, this process is called an emulsion, which is used to create items like mayonnaise, albeit not with soap molecules. Now with all the dirt and grime off of your hands, water is then able to wash all the germs away that we’re stuck underneath the grime, leaving you with squeaky clean hands. So as long as you properly wash your hands for the appropriate amount of time, washing your hands with soap is an extremely effective method of keeping your hands clean and COVID free.
When it comes to keeping your hands clean on the go, hand sanitizer is the tool of choice for most people. Going about your day in a COVID world, your hands touch a plethora of things throughout the day, and to stop the spread of COVID; it is your prerogative to apply hand sanitizer whenever you can. However, not all hand sanitizers are made equal. For the most part, the efficacy of hand sanitizer is based on alcohol content. The magic number to look for with hand sanitizer is that it is comprised of 60% or more alcohol. As an ingredient, alcohol is fantastic at killing germs, pathogens, and of course, COVID-19. During the pandemic, billions of hand sanitizer stations have been set-up across the world, and tens of thousands of companies have started to produce hand sanitizer.
However, as effective hand sanitizer is at killing COVID-19, there are definitely some downsides to hand sanitizer. Surprisingly, hand sanitizer usually kills fewer germs than soap, especially when you wash your hands properly. When you use hand sanitizer, it does not actually “clean” your hand. Yes, it does kill germs, but it fails to wipe away the oil, grime, and sweat that traps the germs on our hands. Therefore, when you use hand sanitizer, especially when your hands are dirty, it’s not as effective as “the kills 99.99% of germs,” you see on the label. So after you eat that greasy meal at the restaurant or a heavy workout at the gym, hand sanitizer alone can’t reach the germs trapped underneath the grime.
Another downside to hand sanitizer is that it requires a considerable amount to be placed on your hand to be effective. The American Council of Science and Health cites that most people fail to use the proper amount of hand sanitizer on their hands 3mL. This is equivalent to a palmful size amount of hand sanitizer you need to place on your hands; the typical “dime size” instructions that Bath & Body Works suggests on their famous small bottle of hand sanitizers are inadequate. Remember that if you carry around the usual 59mL bottle, you should be running out after every 20 applications. The same study suggests that the rule of thumb is that 90% of your hand should be covered for 10 to 15 seconds for hand sanitizer to be effective. Which hints at another problem - when we use hand sanitizer - we tend to wipe it off before it can do its job. Just like the required time needed to wash your hands, the hand sanitizer you put on your hand needs time to soak.
As for your skin, too much hand sanitizer is definitely harmful. In skincare, products that are “alcohol-free” are frequently labeled throughout the industry because alcohol is known to dry your skin, especially the upper layers. Now the solution for this is to moisturize afterward, but since you’re not cleaning the grime from your hands, using moisturizer just creates another layer that can potentially trap those germs. So my advice is when you get a chance to wash your hands, you should do so, and then quickly apply moisturizer afterward to negate the drying effects of hand sanitizer.
Even with these downsides, let’s be clear here. Hand sanitizer made with 60% alcohol or more is VERY EFFECTIVE. When it comes to hand hygiene, hand sanitizer does a great job of keeping your hands largely germ free and killing Covid-19, but it should not be your one-stop solution to keeping your hands clean.
The winner of this debate is clear. Always wash your hands with soap if you’re given a choice between the two options. Hand sanitizer is not an effective enough tool to keep your hands clean. It does not clean your hands. It just kills germs that aren’t trapped underneath dirt and oil. However, it is useful in a pinch and should continuously be used when you don’t have access to soap and running water. Meanwhile, thoroughly washing your hands with soap for 20 seconds gets the complete job done.
In today’s world, where hand sanitizer stations are everywhere, don’t be fooled into thinking that your hands are clean all the time. To achieve ultimate hand hygiene, wash your hands.
Let’s keep up the COVID-19 fight with the ultimate weapon for hand hygiene - good old soap and water.