Nothing says holidays like the smell of cinnamon, so it's a great way to go if you're thinking of creating diffuser blends. However, at Vinevida, we sell two types of cinnamon oil, leaf, and bark. Unexpectedly, they are very different oils.
Now, generally, I'm not a chemistry boffin. I understand it, but there are other ways of working out what oil does. However, it's fascinating to look at when you think about essential oils that come from different parts of a plant. Cinnamon is an excellent example of this.
Today I thought we could investigate the relative cinnamon leaf essential oil benefits versus cinnamon BARK essential oil benefits. How are they different, and how are they the same?
The first place we need to visit is the GCMS report.
What Is A GCMS Report
The properties of any essential oil are determined by what chemicals are in it. We can identify what these are by using a GCMS report.
GC/MS combines the features of Gas Chromatography (GC) and Mass Spectrometry (MS) to analyze volatile and semi-volatile compounds in sample mixes. If you look at the GCMS reports, you can see that cinnamon bark and leaf oils are incredibly different. There are very few correlations in their chemistry.
Since there are no legitimate standards around essential oil quality, GC/MS analysis is generally considered the most accurate analysis of what any essential oil available looks like chemically. The GCMS also tells how much of each chemical exists in an oil sample. Incidentally, to find the GCMS reports for Vinevida oils, head on over to the product listing, scroll down to just under the picture, and you'll find them filed under documents.
The GCMS report for cinnamon leaf tells us that the three most represented chemicals are:
- Eugenol - 50.97%
- Trans Caryophyllene - 40.91%
- Alpha Humulene - 4.60%
Between them, they make up over 95% of the oil. Then, of course, there are many others, but none are more than trace elements.
Cinnamon bark essential oil, then, what does that look like?
- Cinnamaldehyde - 68.26%
- Benzylbenzoate - 8.32%
- Benzaldehyde - 5.11%
These aren't just slightly different; they are radically so. There is a bit of Eugenol in the cinnamon bark oil, but it only comes on the list at 4.01%.
Some chemotypes may be more dramatically different than that even. For example, the essential oil of cinnamon bark is characterized by an abundance of cinnamyl aldehyde (65–80%) and a low amount of Eugenol (5–10%). On the other hand, the essential oil obtained from cinnamon leaves is rich in Eugenol (10–95%) and has low levels of cinnamyl aldehyde (1–5%) (Brochot, 2017).
So the best place to start then is to explore what Cinnamaldehyde is.
Also Read: What Is Cinnamon Essential Oil Good for?
Well, the first thing to say is that Cinnamaldehyde is the main constituent contributing to the smell of cinnamon. So, if you want to fragrance your pine cones, for example, you'll need essential oil for cinnamon bark. Cinnamon leaf is rich in Eugenol, which is the main contribution of clove essential oil. Thus, you'll still get a familiar spicy fragrance, but this one smells more like cloves.
One of the differences that dictate the differences between herbs and spices is the actual sensation of spiciness when we eat them. This is a biological action caused by an action on channels in every cell in the body, the TRPV channels. We've spoken about these before when we have spoken about pain messaging. They transmit messages about heat and pain. Spices make us feel warmer by triggering the TRPV1 channel capsaicin activates when we eat chili. Cinnamaldehyde and Eugenol activate this same channel meaning both oils will warm you. They can be used partly to calm the pain, especially in people experiencing chronic pain who have become weakened over time.
Cinnamaldehyde is a helpful chemical that can be used in many ways but is a severe dermal irritant. For that reason, we use cinnamon bark oil in extremely low dilutions. According to Tisserand and Young, 0.05% would be enough in any blend. We'll look at that a bit more near the end of the post.
Its most important functions are antimicrobial, antibacterial, antifungal, and insecticide properties. It achieves many of these through the same shikimic pathway we spoke about in the star anise essential oil article. However, this pathway does not exist in human biology. Instead, plants use it to attack fungi and bacteria that attack them. Because we don't have it in our bodies, agents that work along this channel mean that fungi and bacteria invasions can be dealt with without potential adverse effects on the human organism. For this reason, these agents have attractive potential as drug targets for both gram-positive and gram-harmful bacteria.
Also Read: Best Essential Oils for Gardening
The differences in these are the way they are constructed and function. Gram-negative bacteria are surrounded by a thin cell wall, which is then surrounded by an outer membrane containing lipopolysaccharide. Lipopolysaccharide means that the cell surface is a permeable barrier. This second layer of defense is the main reason Gram-negative bacteria often develop resistance to many antibiotics. (Bertani, 2019)
Gram-positive bacteria don't have a second outer membrane, but they protect themselves because their inner membrane is made of many layers. It's much thicker than is found in Gram-negative bacteria.
This thicker membrane usually means fewer porous spots for antimicrobial agents to enter. It's why gram-positive bacteria are more resilient against plant extracts than gram-negative ones. (Vasconselos, 2018)
Few agents are efficient against gram-positive and gram-harmful bacteria, but Cinnamaldehyde is.
Cinnamaldehyde has two isomers, cis and trans. Isomers are compounds with the same number of atoms but differ by the way these atoms are arranged. The Trans (E) isomer is the most predominant in nature. Cinnamon bark's antibacterial activity is mainly down to trans Cinnamaldehyde. It targets bacterial cell membranes, which cause them to leak DNA, RNA, and proteins from the cell. When this happens, it becomes much more challenging for the cell to replicate. (Vasconselos, 2018)
Considering that, let's look at some of the things the scientists have found when they have been looking down the slides of their microscopes.
Also Read: Best Essential Oils for Toenail Fungus
What Is Cinnamaldehyde Good For?
First and foremost, bacterial infections.
Staphylococcus aureus is a Gram-positive member of the Bacillota bacteria. It is a member of the naturally occurring microbiota of the body. They are often found on the skin and in the upper respiratory tract. Staph aureus is a serious threat to soft tissue diseases such as cellulitis and abscesses. In some cases, it can also be a cause of pneumonia.
E-coli lives naturally in our guts, but if it gets onto foods, it can cause food poisoning. E. coli infection causes approximately 265,000 illnesses in the United States and around 100 deaths annually.
Enterobacter species are responsible for causing many infections caught in hospitals and less commonly community-acquired infections. These include respiratory infections, soft tissue infections, urinary tract infections (UTIs), osteomyelitis, and endocarditis, among many others. E. aerogenes is found naturally in our gastrointestinal tract. It generally doesn't cause disease in people who are otherwise healthy but can be problematic to people in ordinarily weakened states.
Proteus Vulgaris inhabits the human and animal intestinal tracts and can be found in soil, water, and fecal matter. It has been reported to cause wound infections, burn infections, bloodstream infections, UTIs, and respiratory tract infections.
Pseudomonas aeruginosa, a gram-negative, antibiotic-resistant bacteria, is often related to hospital-related infections such as sepsis. It's a highly advanced organism that can thrive on almost any surface so it can live quite happily on surgical instruments, medical instruments, and catheters, for example. As such, cross-contamination with this bacteria is rife. It can be fatal if it does colonize the lungs or urinary tract.
Every bit as awful as it looks. Get infected with Vibrio cholera; you've got cholera. Cholera is an acute diarrheal illness caused by infection of the intestine with Vibrio cholera bacteria. People can get sick when they swallow food or water contaminated with cholera bacteria. An estimated 1.3 to 4 million people worldwide get cholera each year. The infection is often mild or without symptoms but can sometimes be severe and life-threatening. Between 21,000 to 143,000 people die from it annually.
V. parahaemolyticus is the primary way people get gastroenteritis after eating raw, undercooked, or mishandled sea foods.
Salmonella Typhimurium is the number one cause of food poisoning, causing around one million illnesses in the United States annually. (Ooi, 2006)
I find it fascinating that one of the most effective agents you can find to wipe down your chopping boards, kill bacteria, and protect against cross-contamination is cinnamon bark, an ingredient most people have in their kitchens.
Cinnamaldehyde as an Anti Fungal
Active against several fungi, including four species of Candida.
Candida species live naturally in the human digestive tract, on the skin, and in our mouths. When yeast levels go out of control, they can cause oral and vaginal thrush and go into the bloodstream.
C. Albicans, C. Tropicalis, C. Glabrata, and C. krusei were all found to be vulnerable to Cinnamaldehyde.
Aspergillus Spp. and One Fusarium Species
Aspergillus species are commonly found in soil, rotting vegetation, seeds, and grains. They can occasionally be harmful to humans. Cinnamaldehyde was active against three aspergillus species and one Fusarium species. Fusarium species are less attractive from a medical point of view and are more useful for agriculture. Fusarium fungi tend to rot crops. (Ooi, 2006)
These pathogenic fungi grow on the skin, hair, nails, mucous membranes, other human body surfaces, and feathers in birds. Dermatophytes cause ringworm and similarly related diseases. Cinnamaldehyde is active against
Trichophyton rubrum - colonizes the upper layers of dead skin and is the most common cause of athlete's foot, fungal infection of the nail, jock itch, and ringworm worldwide.
Again, it can cause ringworm.
It causes ringworm and Tinea capitis, which makes your hair fall out. (Ooi, 2006)
Cinnamaldehyde is a Multi-action pesticide used to control downy mildew, powdery mildew, aphids, and mites and is also used as a mammal repellant. Thanks to research done by Michigan State University, amidst all these great uses for the garden, no adverse effects have been identified for bees. (Michigan state university)
Importantly, it has decisive actions against Aedes Egyptus, a mosquito seen as a primary vector of malaria, yellow fever, and dengue flu.
Rodent trials also showed that Cinnamaldehyde has potential antidiabetic effects, having helped to stabilize blood sugar and fats in the blood like cholesterol. (Subash Babu, 2007), (Zhu, 2017) Disappointingly, I don't think eating cinnamon buns every day can get rid of diabetes, but if anyone sees a clinical trial where they want someone to try, let me know, will you? It's a dirty job, someone's got to do it, and I love a cinnamon bun or six.
As Ever, a Pragmatic Reality Check
To put all of this into a little context, cinnamon bark is not the most generous source of Cinnamaldehyde. Vinevida Cassia essential oil also has even higher levels of Cinnamaldehyde at 74%. As such, this makes for an even more vicious essential oil on the skin, but oddly, it smells even more cinnamon-y than cinnamon!
Before we get all carried away about how we're going to heal the world with cinnamon, as ever, there is a "but…"
Sadly, transcinnamaldehyde is a volatile chemical. When exposed to air, it quickly evolves into cinnamic acid, which doesn't have these same properties.
In the same ways, Cinnamaldehyde is unstable in the blood (Vasconselos, 2018) So, whilst we can use it as an antibacterial agent, one of the reasons it has thus far not been developed as a pharmaceutical is that its properties are brief lived and are not considered likely to be stable enough to replicate on a huge scale. Cinnamon is excellent support at home, but despite all these fantastic actions can't quite go into hospital settings yet.
Also Read: Essential Oils for Breastfeeding
Cinnamon Leaf Essential Oil
What Is Eugenol?
Well, it's predominately found in clove oil. If we look at the GCMS report for clove, it's interesting to see how the cinnamon leaf is quite similar to clove oil, whose chemistry is dominated by the same three. Vinevida Clove essential Oil looks like this:
- Eugenol - 74.53%
- Caryophyllene (E) - 12.53%
- Alpha humulene - 3.66%
So even if we take a bird's eye view, even without knowing anything about the oil, we can see that cinnamon leaf oil is more likely to have similar properties to clove oil than cinnamon.
Last year, an article published in the International Journal of Molecular Science described how Eugenol had demonstrated various antioxidant, analgesic, antimutagenic, anti-platelet, antiallergic, anti-swelling, and anti-inflammatory properties. (Ulanowska, 2021)
However, there is a downside because it is a dermal irritant despite the molecule's widespread benefits. It's used extensively in dental products, and many dental technicians have reported developing contact dermatitis. Perhaps more interesting and useful to note is that Eugenol can also cause contact gingivitis and burning mouth syndrome.
Eugenol has demonstrated antibacterial properties against many species, such as Staphylococcus aureus, Pseudomonas aeruginosa, and Escherichia coli. We saw all of those in the cinnamaldehyde section.
It has demonstrated activity against Klebsiella pneumonia, which is associated with hospital-related infections such as meningitis and blood infections like sepsis and pneumonia.
Eugenol was also found to inhibit the spread of listeria.
Eugenol and Viruses
Where cinnamon leaf becomes interesting is that in addition to its antibacterial skills, Eugenol also has tremendous antiviral abilities.
Let's think about that for a second. Examples of bacterial infections include ear infections, strep throat, whooping cough, and urinary tract infections (UTIs). Viral infections include the common cold, flu, coughs, bronchitis, and chickenpox; however, these are viral.
If in doubt, remember the B's go together. If it's a bacterial infection, we use bark. Cinnamon bark has some viral indications, but the leaf will be much more effective.
Be clear on what antiviral means.
Antiviral means it slows the proliferation of the virus. Viricidal means it stops you from catching something. An excellent way to remember is that we use viricides outside of the body as disinfectants, for example.
Herpes Simplex Virus
HSV1 is passed orally and usually manifests as oral herpes and cold sores but can also present as genital herpes. HSV2 causes genital herpes and sores around the genitals and rectum.
Eugenol is antiviral to herpes simplex virus and is also remarkably viricidal since it prevents the enveloping of the virus in both in vitro and in vivo experiments (Benencia, 2000). It limits infection and prevents it from spreading through the body. This applies to both HSV-1 and HSV2.
An excellent 2014 Canadian trial assessed how essential oil vapors inhibited the influenza virus; Bergamot, eucalyptus oil, and the isolated compounds citronellal and Eugenol were very active against the influenza virus following exposures of only 10 minutes. Eugenol was the most effective and killed 100% of the virus after 10 minutes. Again though, to be clear, this was in a petri dish. (Vimalanathan, 2014)
Interestingly, Eugenol might also be developed as a valuable therapeutic for COVID-19 because it can target specific genes.
SARS-CoV-2 binds to the enzyme 2 (ACE2) utilizing a spike in the virus protein known as S1. (Lai, 2022) Spike S1 binds to ACE2 to enter the cell and initiate COVID-19. (Paidi, 2021) Euganol suppressed S1, inhibiting the entry of the virus into cells. In a preliminary mouse trial, Eugenol inhibited the release of several different inflammatory markers. It reduced lung inflammation, decreased fever, and improved heart function. (Paidi, 2021)
This was a mouse trial, and the Eugenol was given orally, which would not be suggested from an aromatherapeutic point of view.
Eugenol has also been found to possess antifungal activity against a range of fungal strains in vitro, including:
Black mold forms on dry fruits. This might make cinnamon leaf a good oil for archaeologists because this mold is also released when you disturb Egyptian mummies!
Trichophyton Rubrum & Trichophyton Mentagrophytes
We saw these earlier. They are the ringworm and athlete's foot baddies.
The post-harvest mold that occurs on citrus fruits
This is in yeast and makes breadmaking possible.
I don't know why you would want to use Eugenol on these next two, so clearly, I am missing a part of the picture.
Interestingly this gilled mushroom is a complete medicine in its own right and is being researched for antioxidant, antimicrobial, antitumor, and immunosuppressive activities.
Edible mushroom is also known as Chicken of the Woods. I can't see any reason you'd want to use Eugenol against this one
Not a harmful thing, but I'm going to mention it here for a completely unrelated reason that's too cool to omit. This mold dissolves gold and is being used in Australia to identify gold reserves. So, if you know someone looking to make a mint doing this and you fancy taking revenge for some undisclosed misdemeanor… Eugenol will properly screw their endeavors!
Safety Concerns of Cinnamon Essential Oils
According to Essential Oil Safety for Health Professionals by Robert Tisserand and Rodney Young, the maximum dilution of Cinnamon Bark Essential Oil is 0.05%. By contrast, they state that Cinnamon Leaf oil is safe for dilutions of 5%...
One of the critical things about cinnamon leaf essential oil benefits versus cinnamon bark essential oil benefits is that you can safely use 10 times as much leaf oil. Personally, though, I'd stop at 3%.
Neither oil would be safe for use in the first 16 weeks of pregnancy, and to be honest, I think if it were me who was pregnant, I think I'd be trying to look for alternatives through the rest of the pregnancy too. Energetically, both cinnamon oils feel a bit aggressive when you are carrying them.
Both oils also have blood thinning capabilities, so you should take care if you have a platelet disorder or are taking blood thinning medications.
An alchemist will always tell you that the whole plant will be more effective than just using small parts. Perhaps no plant shows that more than cinnamon. It's fascinating to think about mildew and insects being attracted differently as they try to attack the plan. There is a whole army of different chemicals protecting it. I've left my favorite to last: Cinnamaldehyde and Eugenol have anti-termite capabilities, with Cinnamaldehyde being the most vital agent. (Chang, 2002) No, sorry, you are not going to destroy this tree. Get outta here, you pest!
So there we have it, the cinnamon bark essential oil benefits are more antibacterial, whereas the cinnamon leaf essential oil benefits are more antiviral and virucidal. Personally, now I'll use cinnamon oils differently. I will be less likely to use cinnamon bark alone. One drop in a lot of carrier oil will do amazing things, but think about how much more you can do if you layer in a bit of the leaf essential oil too. It will have far more antimicrobial effects and smell even more like holiday cookies than either of them do alone! Look at our post about different ways to use the cinnamon leaf and cinnamon bark essential oils.