Essential Oils 101 – All Your Questions Answered

I wanted to pull the “meat” from my first Essential Oils 101  and FAQ pages post and put it here, along with other stuff I have learned since first posting those pages. I hope this will help you learn more about essential oils so you will feel comfortable using them.

If you don’t see your question addressed, please comment with your question and I will do my best to answer it :)

What are Essential Oils?

The short version of this answer is: essential oils are highly concentrated components of plant matter. These components are classified into chemical families (groups), which have their own therapeutic properties, effects, and safety concerns.

Fragrance oils are not to be confused with essential oils, and should not be used for healing.

How are Essential Oils made?

Although different parts of the plant (fruit, herb, tree, etc.) are used, most essential oils are the result of steam distillation. Under the right pressure and temperature and over a period of time, oils vaporize out of the plant matter and are collected. The water remaining is collected and sold as a hydrosol. Although a much weaker product, hydrosols contain the water-soluble properties of the plant matter. They are safe enough to be used on children and pets without dilution.

Citrus oils are most often a result of cold pressing the rinds, although you can purchase steam-distilled citrus essential oils.

Absolutes, which aren’t technically “essential oils” are the results of using solvents for extraction. High-quality absolutes leave little solvent in the end product.

CO2 distillation is a new method, where CO2 is used instead of water to extract essential oils. This method is considered superior to steam distillation.

What labels should I look for when purchasing an essential oil?

Therapeutic Grade

When it comes to labels, anything is fair game. “Therapeutic grade” is a term anyone can use, because it is a generic term. It means nothing as far as certification goes, as there is no certification body that exists. Some companies have cleverly marketed their labels to make you think they are unique or have some sort of official approval, but this is not the case. I don’t fault them for that, that is part of business and marketing. One company uses “Certified Pure Therapeutic Grade” as a label – but this is their own certification. Anyone can make their own oils and slap a “certification” on their own labels – but what does that prove? Nothing, since they are slightly biased ;) Maybe some day there will be some board of advisers who can give out approval status to oils who meet certain qualifications, but so far there is none.

What you want to make sure is that the bottle doesn’t say “fragrance oil.” That would be an artificial scent, not a therapeutic (healing) oil.


Unfortunately, you can  have “Pure Tea Tree Oil” that is only 10% tea tree and 90% vegetable oil. It’s sadly another marketing trick used, and they get away with it because there is no official certification process.

Even if it does contain 100% of an essential oil, the quality can be very poor.

For example, when lavender is grown, the end product is considered “pure” even if soil conditions were bad, the temperature was not ideal, the lavender sat around for a long time before being distilled, the type of distillation, the storage conditions of the essential oil, and many more factors. You can have a “pure” end product that is very low quality (I discuss this further down).


A label I like to see, especially with citrus, is Organic. Due to the processing used (remember citrus rinds are pressed to release the oils) pesticides are on the rinds and therefore get into the oil and on my skin (or breathed into my lungs).

Anything I put on my skin I want free of contaminants, so organic is a good choice. That said, in light of recent test results, we found no contaminants in 4 essential oil companies which were not labeled organic. If you are using an oil for cleaning your home, it likely doesn’t matter if it is organic or not. However,  if there are oils you use frequently on your skin, or even inhale frequently (and especially if you choose to use them internally), then I would recommend you go with organic. Essential Vitality and J&M Botanicals are organic, and Mountain Rose Herbs and Aura Cacia have organic options.


That said, “wildcrafted” can be just as good, if not preferred, over “organic.” It depends on where it is grown. If a wildcrafted product is grown in its natural habitat, the therapeutic properties can be better than an organic one which may be better “controlled” yet not as good an environment. It’s good to know what you are dealing with.

For External Use Only

“For external use only” is a label that does in no way indicate the oil is not pure, safe to use, or low quality. Many high-quality oils are not safe for internal use – ever. Often this label is used by companies who are trying to be sure people don’t get harmed (like the “do not use while bathing” label your hairdryer has) and not because they know their oils are polluted. They don’t want the liability risk. Too many people purchase essential oils without first researching how to use them safely.

Because traditional aromatherapy focuses on external use (inhalation and topical use), companies use this label to keep them safe from liability. Many oils are not safe for internal use, and since many people don’t take the time to first educate themselves on the oils, people can get hurt – children being the most vulnerable.

Realize that if it’s safe enough to breathe in and apply to your skin, it’s safe to use internally (if it’s an oil that *can* be safely used internally). Just don’t diss the whole product line due to this one sentence.

Bottom line: Educate yourself before using :)

How do I know if the Essential Oils I am using are good quality?

There are so many variables that come into play when it comes to quality essential oils. We certainly want high quality oils so they are most effective when we use them. Ability to heal (therapeutic properties) and the aroma itself are affected by the following:

  • climate and altitude where it was grown
  • quality of soil
  • amount of rainfall
  • temperature
  • how it was harvested
  • how it was stored prior to distillation – or in the case of citrus, pressing
  • time elapsed between when it was harvested and when it was distilled
  • the parts of the plant used – leaves, flowers, roots, etc.
  • type of distillation equipment used (copper? steel?)
  • storage conditions of the oil after distillation, as well as how long it sat before the consumer purchased it

Regardless of the above factors, once an oil is distilled it is considered “pure” no matter the quality.

Adulterations and tampering can be done after the pure oil has been made. This could mean:

  • blending a high quality (more expensive), yet pure essential oil with a lower-quality (less expensive) essential oil of the same name.
  • blending the pure essential with another, lesser quality oil such as vegetable oil
  • adding specific (natural or synthetic) constituents to a lower-quality oil to “improve” on the oil medicinally or aromatically. An example of this would be adding linalyl acetate to a low-quality lavender essential oil. Pure? Yes. Quality? Hmm.

So how do we know the quality? We can tell by looking at the bottle. Reputable companies will have a GC/MS available, although they are not always updated.

What Essential Oil companies provide quality oils?

We did our own testing on five companies in April and can recommend all five:

  1. Essential Vitality
  2. Aura Cacia
  3. Mountain Rose Herbs
  4. doTERRA
  5. Young Living

Read more: Essential Oil third-party testing Round 1 to find that you don’t have to purchase the most expensive brands to get the best results.

We currently have 10 more brands out for testing and should have results soon. I’ll update here when we have those results.

Do some Essential Oil companies have exclusive oils?

Essential oils are sold online, in heath food stores, and through direct sales companies. All of them purchase from distillers who make the essential oils, and many of them purchase from the very same ones.

Myrrh is one essential oil that is only sold in two or three areas of the world. It’s pretty likely any Myrrh you purchase is from the same place.

Now what a company does with the oil once they purchase it is another story. If they choose to dilute it, or otherwise tamper with the quality, that is up to them.

Some companies do make their own blends that are exclusive to them. However, there are alternatives. Young Living has a Thieves blend, and doTERRA has a similar blend called OnGuard.

Since Essential Oils are “natural,” they can’t harm you, right?

Wrong. Essential Oils are very potent, highly concentrated versions of their wild counterparts. Many are 100 or even 300 times more potent than extracts. Because they are so concentrated they almost always need to be diluted before use. One drop per teaspoon is a good idea of how much dilution they need (more info here).

As for the “can’t be harmed” part – don’t be fooled! Many essential oils can be deadly or make you sick if ingested or if too much is absorbed by your skin at one time. PLEASE PLEASE PLEASE educate yourselves before purchasing any essential oil to be sure you know how to use it first. Keep a reference guide handy, and refer to it often. The Encyclopedia of Essential Oils is probably the best choice if you want one book that has it all.

Always keep out of the reach of children. Treat them as you would any other potent medicine.

How can I use essential oils?

There are several ways essential oils can be used:

If you are trying to improve a mood or calm emotions, aromatic use is your best option. The molecules are small and are effective when diffused or breathed in.

Headaches, for example, can be effectively driven away by inhaling Peppermint. Mental activity can improve by diffusing Rosemary. Sinuses can be opened by inhaling Eucalyptus. And more.

Use a diffuser, apply to a clay pendant, or simply put a few drops of oil on a cotton ball. Applying calming oils to pillows and bed sheets can make for a relaxing night’s sleep.

Aromatic use is very effective and often under-rated!

If you are dealing with a wound, wanting to nourish your skin, or treat a fungal infection, then of course go with topical. Because not all of the molecules in the essential oils reach the blood stream, it is difficult to over-dose using this method.

Most oils need to be diluted before applying to the skin (read dilution advice here). Mixing with a carrier oil, not water, is advised, because as we know – oil and water do not mix. Good carrier oils for most uses are sweet almond, jojoba, or avocado oil. Coconut oil can be used for its anti-bacterial and anti-fungal properties that can enhance the healing properties of oils you may choose to sooth cuts and scrapes. Coconut oil is also thicker and will last longer than a liquid oil. It’s all a matter of preference, really. Keep in mind liquid carrier oils can go rancid within a few months if not refrigerated, or in a year if kept in the refrigerator. Consider this when determining how large a batch you want to pre-mix. Jojoba and coconut oil last the longest.

It is very important to understand, most oils are not safe for ingestion, regardless of quality, except in special circumstances. I would only ever recommend internal use under the care of a professional and only under special circumstances where topical use would not be effective. I personally can not come up with any scenarios which would warrant frequent internal use. Essential oils are very concentrated and very potent, and have been known to cause disruption in the guts and strip out the good bacteria due to their potency – not to mention burn and scar the delicate skin inside your body. The closest I would go with “internal” use is using essential oils for oral care.

Back to my “regardless of quality” statement…

I have heard a few different people say “I only ingest oils that are pure, because they are the only ones that are safe” the same time they are telling me “they are so potent you only need one or two drops instead of three to five.” Please explain to me the logic here…because it sounds to me that the more potent an oil is, the more reason there is to dilute it. Jessie Hawkins of Vintage Remedies has the same take on this – and she is much more qualified than I am to speak on this subject.

Make sure you know whether or not the oil you are ingesting is safe for internal use. Although some are “generally regarded as safe” (GRAS) by the FDA regular ingestion of essential oils is not recommended for long-term use.

For more information, I highly recommend Robert Tisserand’s book, Essential Oil Safety. The second edition is coming out in September.

Bottom line: be careful. Proceed with caution, and go with your gut.

How long do Essential Oils last?

When essential oils have a high cost, we want to believe they will last “forever.” This isn’t really true. Essential oils are volatile, which means they diffuse into the air. The more often you open a bottle, the faster constituents in the oil will evaporate – the lighter ones floating out first.

The shelf life of essential oils can vary depending on storage conditions and the type of essential oil, both of which are out of our control. However once we obtain the oils, there are some things we can do to make sure they last as long as possible:

  • keep the bottles cool, even to the point of refrigerating them if possible (I have mine in a converted wine fridge)
  • keep them out of light, in a cabinet preferably
  • close them tightly after each use

There is a wonderful list on Aromatics International showing shelf life from time of distillation for many different oils. Citrus oils seem to spoil more quickly (1-3 years), with “woodsy” oils lasting up to 8 years or longer.

Always discard oils which have thickened, appear cloudy, or smell “off.”

What are some good books for learning more?

Here are some books I recommend:

And all the articles I have written on essential oils are here: Essential Oils.

I am serious about educating myself more in-depth. What courses do you recommend?

There are many wonderful resources out there. Here are some of my favorites:

What diffuser do you recommend?

I got by without a diffuser for months. Once I got one I wanted to throttle myself! It’s running almost all the time now. I love using brain-sharpening essential oils in it while I work at my desk, and it’s wonderful for calming oils in the evening. My favorite one is the SpaVapor, which is a cool mist so the essential oils aren’t damaged by heat. Aura Cacia has one similar (but doesn’t light up). VaporEze is helpful for smaller rooms for a pleasant aroma. I also like my car diffuser.

What brands do you recommend?

These are the brands I can recommend based on our first testing results:

We have more currently being tested and I will update here when I have those results.

Did you learn something? Do you have any questions for me? Comment below!

Want to learn more about herbs?

proud contributor
Lea Harris founded Nourishing Treasures in 2006. A mom passionate about her family's health and well-being, Lea believes education is power. Encouraging others to take baby steps in the right direction of health for their families, Lea's goal is to raise awareness of what goes into our mouths and on our bodies, providing natural alternative information that promotes health and prevents disease by using traditional foods and nature's medicine.

Lea is a Certified Health Coach graduate from Beyond Organic University, and a Certified Aromatherapist graduate from Aromahead Institute.

"Like" Nourishing Treasures on Facebook, join the Nourishing Treasures Group on Facebook, follow @NourishTreasure on Twitter, and subscribe to our newsletter.

You can also find me on Learning About Essential Oils forum, and Fido Fermentation Facebook group.

Disclaimer: I use affiliate links wherever possible. So if you click on a link, and make a purchase, I might make a small commission, but it doesn't cost you any more.

Comment with Facebook


Leave a Reply