First off, what makes my blog posts about essential oils different from others? Probably not much. What are my credentials? Also not much. I am a mom. I am a library clerk. I do not hold any science degrees from any university. I like looking at the butt of science when it walks by. I am a perpetual student of MOOCS and am married to an MD/PhD student studying genetics and psychiatry. I have no affiliations with any essential oil distribution companies. I have many “oily” friends as well as friends in the fields of science. I am fascinated in the improving of communications between scientists, doctors, and the average layperson like myself. I do roll my eyes/facepalm/headdesk but will do my best to keep it to myself because such public displays of vitriol or insults of persons only do more harm and widen the gap.
So, with basic introductions out of the way, the first discussion topic is:
What is an essential oil?
I would love to find some plant biologists or chemists to answer this but you’re stuck with just little ol’ me. Simply googling this question brought up many hits. I am not one to choose the first link provided nor go with just one source and neither should you. And remember, I’m trying my best to avoid information coming from possibly biased sources (i.e. no DoTerra, Young Living, Rocky Mountain, etc. affiliations). Of course, as humans, we all have inevitable biases we must deal with. Google also doesn’t always help as, over time, it’s algorithms will pay attention to your search parameters and tailor to you. What I get vs what you get will vary. Hubby calls it google-fu.
Wikipedia was the eighth down in the results for the basic question of “what are essential oils?” During my college days, professors often would say “don’t use Wikipedia in your research papers!!!!!” Even Wikipedia says it needs more citations to reliable sources on the essential oils entry but it’s a decent jumping off point:
An essential oil is a concentrated hydrophobic liquid containing volatile aroma compounds from plants. Essential oils are also known as volatile oils, ethereal oils, aetherolea, or simply as the oil of the plant from which they were extracted, such as oil of clove. An oil is “essential” in the sense that it contains the “essence of” the plant’s fragrance—the characteristic fragrance of the plant from which it is derived. The term essential used here does not mean indispensable as with the terms essential amino acid or essential fatty acid which are so called since they are nutritionally required by a given living organism.
Direct link to source: https://en.wikipedia.org/wiki/Essential_oil
Hydrophobic means it is repelled by or will not mix with water. As for volatile, it easily evaporates. Meaning yes, your bottle of essential oil will not last forever. I know this because I had a small sample vial and it evaporated before I could use it all. I can still smell a residual but of essence but there is no oil in the vial.
In essence (haha), essential oils are the odoriferous liquid essence of a plant. That answers that question from a biological standpoint.
Are essential oils really the life blood of plants and what role do essential oils play in plant biology?
This is shared mostly by bloggers, distributors, and the companies who market essential oils. I’m looking for a more scientific source to answer this question as it sounds somewhat implausible. (Spoiler alert: it is implausible.)
One website in my search was Essential Oils University, put together by Dr. Robert Pappas, who holds a PhD in chemistry and teaches at Indiana University. (Acceptable credentials, in my opinion.)
…essential oils do not have the same function in the plant that blood does in the human body. Our blood primarily performs the function of circulation and transport of oxygen and nutrients to the all the cells and organs of the body. Essential oils do not play this role in the plant.
The truth is that essential oils are an end product of the plants metabolism and emitted by the plant not circulating within the plant like blood in the body (see magnified picture of oil glands on Roman chamomile leaf). Think about what some of the end products are from human metabolism and, if you want a more accurate analogy, well you get the idea. I realize it wouldn’t be as marketable to use a tag line like “the excrement of the plant” but that would be more accurate than the “life’s blood.”
So… essential oils, thus named because they are the volatile essence of a plant… could be compared to excrement? I can see how that wouldn’t market well! I can see how complicated the physiology of plants can be but to say essential oils are the lifeblood of the plant would be incorrect.
Essential oils in plants can serve diverse functions, depending on the plant – aromatic attractors or repelants, injurious excretions (sap), or simply byproducts of waste. (http://www.faculty.ucr.edu/~legneref/botany/essoils.htm) From Britannica Encyclopedia’s entry:
The function of the essential oil in a plant is not well understood. Odours of flowers probably aid in natural selection by acting as attractants for certain insects. Leaf oils, wood oils, and root oils may serve to protect against plant parasites or depredations by animals. Oleoresinous exudations that appear when the trunk of a tree is injured prevent loss of sap and act as a protective seal against parasites and disease organisms. Few essential oils are involved in plant metabolism, and some investigators maintain that many of these materials are simply waste products of plant biosynthesis.
Source link: https://www.britannica.com/topic/essential-oil
In conclusion (or my TL;DR)
Essential oils are aromatic oily essences from plants. Their physiological purpose to the plant in which they come from may be to attract, repel, or repair, or simply be the byproducts of plant waste.
Stay tuned as I continue my search to learn more about the science behind essential oils. Feel free to leave me a comment!