February 2015

Do essential oils like thieves really kill germs?

From an article posted by Annie Pryor, PhD.

New Hand Sanitizer Results posted 2/22/2105

Essential oils are very popular these days. They are believed to do everything from boosting the immune system to reducing anxiety to getting rid of acne. In fact, there is an oil for just about anything you want to do with the possible exception of creating world peace. But how much scientific evidence is there to support these claims? I decided to do some experiments myself. I cannot do experiments to determine whether or not essential oils really cure the flu or improve blood pressure. However, I can tell you whether or not they really kill bacteria. (I cannot test for viruses.)

If you would like to be alerted when new experimental results are posted, please like the Essential Oil Experiments Facebook Page that I made. I’ll post on there anytime I put new results up here.

If you are new to my website, let me tell you a little about myself. My name is Annie Pryor. I have a Ph.D. in biochemistry from The Ohio State University. After a few years working in a research lab, I “retired” to be a stay-at-home mom. When my first baby got a terrible stomach virus that required a trip to the ER, I decided to research the subject and created this website dedicated to reducing the prevalence of the stomach “flu” in the world. I still get a hankering to do experiments now and then. I’ve tested hand sanitizers, cleaning products, produce washing techniques and even lunch box coldness. I don’t as of yet use essential oils myself, and I don’t sell essential oils. I am not an oil expert, and I always thought they probably didn’t do anything (until getting these experimental results).


My research is not supported or affiliated with ANY of the essential oil companies. In fact, they are all pretty mad that I am doing it. The FDA would like you to all know that Essential Oils are not allowed to claim that they treat or cure any diseases or conditions. I am in no way implying that essential oils “Stop the Stomach Flu” because that is the name of my website. I do not use or sell essential oils. I am not a medical doctor and nothing I say should be taken as medical advice. Always follow the manufacturers directions when using essential oils, cleaners, hand sanitizers, and any other product in the world. And don’t let children play with plastic bags or get near the hot stove. Got it?

Most of these are simple experiments and you can repeat them yourself if your child needs a great science fair project. In fact, there are even child sized disposable latex-free gloves called Glovies that you can buy so your kids can do most of the work with their science fair project. Those glovies are also super useful for crafts and other messy kid projects as well. You can also buy the same ready-to-use agar plates that I use on amazon. I describe my homemade incubator on the page about hand sanitizer experiments.

Does Thieves oil kill bacteria?

The first essential oil that I have tested is Thieves Oil made by Young Living. Thieves oil is a blend of clove flower bud oil, lemon rind oil, cinnamon bark oil, eucalyptus radiata leaf oil, and rosemary leaf oil. I purchased the oil from http://www.striveforhealthy.com/. (Do not buy any Young Living Oils on amazon. Young living sellers are not allowed to sell on amazon so most of the Young Living oils on there are counterfeit.) Thieves oil is said to boost the immune system and kill germs. It smells heavenly, sort of like a gingerbread house at Christmas.

The first thing I did was determine whether or not there was any bacteria in the thieves oil or olive oil that I was using. To do this I put some of the oil on a sterile swab and rubbed it all over an agar plate. I purchase all my agar plates from amazon. I let the plates incubate overnight in my 98 degree F incubator. As you can see, nothing grew on the oil plates so there is no bacteria in the oils.

For the big experiment, I tested thieves oil with other oils and cleaners to compare. I tested olive oil, coconut oil, smart balance oil, white vinegar, apple cider vinegar, and chlorine bleach. Since thieves is recommended to be used in a 1:4 dilution with a carrier oil, I also tested the mixture of thieves and olive oil. (I put 1 teaspoon of thieves oil in a bottle with 4 teaspoons of olive oil.) First, I thoroughly cleaned my kitchen countertop. Then, I used masking tape to section off squares of my kitchen island. I labeled the squares according to what I would put in each square. (Dirty +control, Clean-control, olive oil, thieves oil, smart balance oil, coconut oil, olive oil and thieves oil mixture, 10% chlorine bleach, 25% white vinegar, pure white vinegar, apple cider vinegar)



Next, I made “germ water”. To do this I got a scoop of dirt from outside and put it in a small cup of water. I poured the mixture through paper towel to get rid of chunks. Then I scrapped off some bacteria from the previous days dirty control agar plate and mixed that into the brown water. Here is the picture of the germ water. It is full of dirt and bacteria.



I put 1.25 milliliters of “germ water” onto each square and spread it around to cover the entire square using my gloved hand. Then I let the squares dry for about 2 hours.



Once the squares were dry, I put 1/4 teaspoon of each test product onto its respective square and used a clean gloved finger to spread them around to completely cover the square. Of course, I put on a new glove for each test product.

I intended to let each “cleaner” sit for 5 minutes on its square. However, I did so many different ones at once that it took too long. Each cleaner sat for 25 minutes. After 25 minutes, I used sterile swabs to collect bacteria from each square and rubbed the swabs all around on the appropriately labeled agar plate. I let the plates incubate for 36 hours in my warm incubator (about 98 degrees F).


This picture shows tons of bacteria growing on the dirty control plate. You also see the clean control plate which should have no bacteria. The 10% bleach plate should also have no bacteria. The apple cider vinegar, 25% white vinegar, and pure white vinegar did not have as much bacteria as the dirty control plate but still have too much bacteria for me to think they are an adequate germ-killing cleaning product. (I do always use white vinegar to clean my fake wood floors, though. It is certainly good enough for that.)

Since the Apple Cider Vinegar contains the “mother”, I wanted to make sure that the apple cider vinegar itself did not contain a lot of bacteria that grew on the agar plate. So, I just tested some apple cider vinegar by itself. There was only one colony on the plate, so no significant amounts of bacteria came from the apple cider vinegar.


This picture shows that the smart balance oil, olive oil, and coconut oil all have less bacteria than the dirty control plate and probably have some bacteria killing ability. Look at the Thieves oil plate! Not one colony of bacteria!


This picture shows the Thieves oil compared to the Thieves oil/ olive oil 1:4 mixture. The diluted thieves oil is not as good at killing bacteria as the pure thieves but it does some killing.

I have repeated this experiment several times already and have gotten the same results. Here are some results from another day. The thieves still did great as did the 3% hydrogen peroxide and Zylast Antiseptic hand sanitizer. Zylast is one of my 3 favorite hand sanitizers for killing norovirus. For a complete list, see the hand sanitizer page.



At first I wondered if the oils were really KILLING the bacteria. What if they were just coating the bacteria so that they couldn’t multiply on an agar plate? What if when you swallowed one, your stomach acid would free the bacteria from its oily prison and it could still make you sick? How do I know that it is really dead? I know that the bacteria on the hydrogen peroxide plate are really dead because the hydrogen peroxide turns into oxygen and water and is really GONE. However, since the Thieves seems to do significantly better than the olive oil, coconut oil, and Smart Balance oil, I really think it is actually KILLING the bacteria. I wouldn’t be surprised if Olive Oil was killing the some bacteria too. Here is an article about olive oil killing cancer cells.

I repeated the experiment again and this time only left the oil sit on the squares for 5 minutes. As you can see, there is just a little bit of growth on the pure thieves plate. I repeated this 5 minute experiment 4 times with the same results. There is just a little bit of growth after 5 minutes. However, time is not the ONLY variable in these experiments. The “germ water” is different every time. It may have different amounts of dirt and different amounts of bacteria from experiment to experiment. So, it may be that sometimes, if there is just too much dirt or bacteria, there will be a little bit alive after treatment with thieves. However, since I’ve repeated this several times, I do think that time plays a role. The thieves seems to do better the longer it sits. I think this is actually a GOOD result. It suggests that the killing is time dependent. This is more evidence that the oil is actually killing the bacteria. If it was just coating the bacteria and stopping it from multiplying, then I wouldn’t think the time difference would matter.

5 minute test


5 minute test


Does Thieves oil work as a hand sanitizer?

A lot of people are diluting thieves oil and are using it as a hand sanitizer. The suggested dilution is 1 drop of thieves oil and 4 drops of a carrier oil. So, I used my thieves oil/olive oil mixture that is in a spray bottle, and I used my 10 year old son’s hands. I used these amber spray bottles from amazon. I was so surprised that they could spray thick oil nicely without clogging. I did the experiments after school before my son washed hands. It would have been nice if he had 4 hands because I wanted to test 4 things. Since he didn’t, I divided up the fingers. I rubbed his thumbs on the dirty control plate. I put olive oil on the first 3 fingers of his right hand. I put the thieves/olive oil combo on the first 3 fingers of his left hand. I put Clorox Hand Sanitizer on both pinkie fingers. I let the sanitizer/oil sit on his fingers for 1 minute, and then rubbed those fingers on the appropriate agar plate. A hand sanitizer needs to work fast because you don’t have much time between putting it on your hands and picking up your sandwich. As you can see, the oils do really seem to kill some germs. However, it doesn’t compare in bacteria killing to the Clorox Hand Sanitizer. I like Clorox Hand Sanitizer because it is one of the few hand sanitizers that actually kill norovirus. (For a list of all my favorite hand sanitizers that kill norovirus, please read this page of my website.) If you aren’t going to kill stomach viruses, I see no reason to use a hand sanitizer at all. Clorox hand sanitizer is not available in stores but is available here on amazon.



I have repeated this experiment several times and am very confident in the results. Here are the results from another day. This time, I just put the thieves/olive oil combo on the left hand and the Clorox Hand Sanitizer on the right. There were only 2 colonies of bacteria on the Clorox hand and significantly more on the thieves/olive oil hand. Clorox Hand Sanitizer does not contain chlorine bleach, by the way.







Comparing Young Living Thieves Waterless Hand Purifier to Zylast antiseptic hand sanitizer

Let me first say that a good thorough hand washing with soap and water is ideal. However, there are times when me must eat but can’t get to a sink to wash hands. For example, my children are not permitted to wash hands before lunch at school. Some teachers claim that hand washing takes too much time. I think that is ridiculous, of course. However, there are times when you need a good hand sanitizer and I’ve been trying to find the best ones. I have already tested many hand sanitizers on this page.

For this experiment, I wanted to determine if the Thieves Waterless Hand Purifier really killed bacteria. I got the Thieves Waterless Hand Sanitizer here. For this experiment, I used my children’s hands and some of their friend’s hands. First they rubbed their thumbs all over the dirty control plate. Using a disposable 1mL syringe, I put .5mL of Thieves Waterless Hand Purifier onto their left fingers and rubbed it in with my clean gloved hand. I let the fingers dry for 1 minute, and then they rubbed their fingers all over the agar plate. Finally, I put .5mL of Zylast antiseptic hand sanitizer onto their right fingers. I rubbed it in with my clean gloved hand. I let it dry for 1 minute and then they rubbed those fingers all around an agar plate. I put the plates in my warm incubator for 24 hours to let the bacteria grow.




As you can see, the Thieves Waterless Hand Purifier did a very good job! It is important to note that these hands did not have ACTUAL DIRT on them. As you will see when you keep reading, most hand sanitizers ( except Zylast) don’t work well on hands with actual dirt. So, if you or your child’s hands are actually dirty, you need to wipe them off with a wipe before using the Thieves Hand Purifier.

Comparing Homemade Thieves/Witch Hazel Spray with Clorox Hand Sanitizer Spray

For this experiment, I made my own Thieves hand sanitizer. I used 15 drops of Young Living Thieves oil, 1 teaspoon Witch Hazel, and 5 teaspoons of distilled water. I put it in this amber glass spray bottle. Since it is a spray, I compared it to the Clorox Hand Sanitizer Spray that I purchased from Amazon. (The Clorox Hand Sanitizer Spray is primarily ethanol and does not contain chlorine bleach.) For this experiment, I had the kids rub their thumbs all over the dirty control plate. Next, I sprayed 8 sprays of the homemade thieves spray all on their left fingers, and I rubbed it in with my clean gloved hand. I let it sit for 1 minute, and then the kids rubbed those fingers all over the agar plate. Finally, I sprayed 5 sprays of the Clorox hand sanitizer all over the right fingers. I only used 5 sprays because that seemed to make the fingers wet enough. I rubbed it in with my clean gloved hands and let it sit for 1 minute. Then I had the kids rub their right fingers all over another plate. I incubated the plates for 24 hours in my warm incubator to let bacteria grow.

As you can see, the homemade thieves spray killed some germs but I don’t think it does enough to be actually used as a hand sanitizer. I wouldn’t trust it. It is also important to note, that these hands all looked clean. They did not have actual dirt on them. As you will see when you keep reading, most hand sanitizers (except Zylast) don’t work well on hands covered in actual dirt.

How does the Thieves Waterless Hand Purifier and the Homemade Thieves spray do in the presence of dirt?

I have done many hand sanitizer experiments in the past (which you can see here) that show that most alcohol based hand sanitizers don’t do well on hands with actual dirt on them. The alcohol just can’t seem to penetrate the dirt. I wanted to know how the Thieves Waterless Hand Purifier and the homemade Thieves Spray do when actual dirt is present. Normally, I would send my children outside to play and then they would come in with dirty hands. However, since there is 6 inches of snow on the ground and the temperature is below zero, this is not an option. So, I tested the hand sanitizers on the dirty countertop, just like I did for the first experiments on this page. I put 1.25 mL of dirty “germ water” on each square, rubbed it all around and let it dry. Then using disposable 1mL syringes, I added .5mL of each hand sanitizer to the appropriate square. I rubbed them all around with a clean gloved hand. I timed them each for 1 minute and then took swabs of the squares. I rubbed the swabs all around the appropriately labeled agar plate. The plates incubated for 24 hours.




As I expected, only the Zylast Antispetic hand sanitizer was able to cut through the dirt. Don’t feel too bad, Thieves lovers. Purell Advanced and the Clorox Hand Sanitizer do not do well in this test either. My advice is that if you use any hand sanitizer besides Zylast antiseptic, wipe dirt off your hands with a wipe before using your hand sanitizer.





To sum up, I am surprised and impressed with how well the Thieves Waterless Hand Purifier killed bacteria in my experiments. We don’t know if it would kill norovirus, though. It is also important to wipe off your hands with a wet wipe before using the hand purifier if you have visible dirt on your hands. The Thieves Hand Purifier also smells WONDERFUL. It smells like peppermint and smells so delicious that you need to be careful that your kids don’t eat it. If you would like to buy Thieves Hand Purifier, you can order it from www.striveforhealthy.com or buy it from another authorized Young Living seller. Do not buy it from Amazon. Many Young Living Products on Amazon are counterfeit.

Clorox Hand Sanitizer Spray has always been a favorite of mine because it is one of the few tested to kill norovirus. It is primarily ethanol and does not contain any chlorine bleach. It dries nicely leaving your hands feeling clean. It is important to wipe off your hands with a wipe before using this hand sanitizer if they are visibly dirty. Clorox Hand Sanitizer is available from a reputable seller on amazon. Of course, I LOVE the “Norophobe Zone” magnet that this pack of hand sanitizer comes with.

Zylast antiseptic is a wonderful product! It kills norovirus and works on dirty hands! Sometimes people complain that it leaves a sticky film. You can order it from http://www.zylastdirect.com/catalog.php. If you use the coupon code “StopNorovirus” you will get 10% off your order. I recommend getting Zylast Antiseptic and NOT Zylast Lotion. The lotion has never been tested for its ability to kill norovirus.


I currently working on testing Ameo Proshield and doTERRA ON Guard to see how they compare with Young Living Thieves. I will also be testing the thieves cleaner. I have a big list of experiments that people want to see. So, check back soon for more results. Also, If you would like to be alerted when new experimental results are posted, please like the Essential Oil Experiments Facebook Page that I made. I’ll post on there anytime I put new results up. Feel free to e-mail me if you have suggestions.

These experiments are very expensive to do. I have spent over $200 on agar plates for just the experiments that I have done on this page so far. I have received $100 in donations which I greatly appreciate. If you happen to be able to make a small donation to these experiments, I would really appreciate it. Most people donate $5. However, please do not donate if you can’t easily afford it. I’ll find a way to do them anyway. I asked my husband for agar plates for Valentines Day.

I am not an essential oil expert. If you have questions about the oils or want to learn more about them, you can e-mail the gal at www.striveforhealthy.com. This is where I bought mine. I got very good customer service and she is very knowledgable.

Please do me a favor before you leave my site. Please read this one page about how to avoid getting and spreading stomach bugs. My main mission is to reduce the prevalence of stomach bugs in the world. That can only be accomplished through education. Please read the page. Don’t be the person who sends your kids back to school because they haven’t vomited in a few hours. Don’t be the person who bakes cupcakes for your child’s class the day after you had a stomach virus. Thank you!

***Donate with PayPal***

–Annie Pryor, Ph.D
phd.annie at gmail.com

Read more: http://www.stopthestomachflu.com/do-essential-oils-like-thieves-really-kill-germs


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