How Long Do Essential Oils Last?
There might be times when you would have bought a bottle of essential oil, used it for a while and kept it in your shelf to use it later. Months or perhaps, years pass by, and you would have completely forgotten about it. So, can it be used now? Or, it has gone bad? The important question is how long do essential oils last?
Well, understand that everything has an expiry date. This applies to essential oils too. Just because they are pure or plant-derived, doesn’t mean they can last for years and years.
So, let’s understand the shelf life of essential oils in detail.
How Long Do Essential Oils Last?
The shelf life of essential oils depends on their chemical structure. While some evaporate or oxidize more rapidly, others take some time.
Most people find it surprising to know that essential oils actually have a shelf life. Just because they are expensive, it doesn’t mean they cannot go bad. So, regardless of what brand you buy or what price tag the bottle comes with, it cannot be used after a certain point of time.
Shelf Life Of Different Essential Oils
As said earlier, the shelf life of aromatic oils depends on the chemical compounds they contain. The major families of essential oils include sesquiterpenols, sesquiterpenes, monoterpenols, monoterpenes, ethers, esters, ketones, aldehydes, oxides, and phenols.
Essential oils containing the above compounds have different shelf lives, which include:
1. Essential Oils That Contain Sesquiterpenes
Essential oils with sesquiterpenes have anti-fungal, anti-bacterial, anti-spasmodic, analgesic, sedative, cooling, and anti-inflammatory properties. These oils have a shelf life of 8 to 10 years and are energetically centering, calming, and grounding. They are admired for their base & middle notes.
Essential oils that are rich in sesquiterpenes include:
- Ylang ylang oil
- Spikenard oil
- Ginger oil
- Myrrh oil
- Black pepper oil
- Cedarwood oil
- Vetiver oil
- Patchouli oil
- German Chamomile oil
- Opopanax oil
2. Essential Oils That Contain Sesquiterpenols
Essential oils that are rich in sesquiterpenols have amazing therapeutic properties. They are usually sedative, anti-spasmodic, anti-bacterial, anti-inflammatory, grounding, immune-stimulating, and skin healing.
Essential oils that are rich in sesquiterpenols include:
3. Essential Oils That Contain Monoterpenes
Essential oils that have monoterpenes in them are natural deodorizers and air purifiers. They can also ease muscle pain and stiffness. Monoterpenes are compounds that are unsaturated, making them unstable and prone to oxidation.
Essential oils that are rich in sesquiterpenols include:
- Grapefruit oil
- Cypress oil
- Siberian fir oil
- Ravintsara oil
- Orange (sweet) oil
- Juniper berry oil
- Lemon oil
- Bergamot oil
- Black pepper oil
- Frankincense oil
4. Essential Oils That Contain Monoterpenols
Essential oils that contain monoterpenols in them are naturally anti-infectious. Besides this, they also have anti-bacterial, anti-spasmodic, anti-fungal, and antiviral properties. These oils are generally non-toxic and mild on both mucous membranes and the skin. They strengthen your immune system, nourish your nervous system, support emotional balance, and great for your skin.
Essential oils with monoterpenols include:
- Thyme oil
- Tea tree oil
- Lavender oil
- Basil oil
- Geranium oil
- Palmarosa oil
- Peppermint oil
- Rose oil
- Rosewood oil
5. Essential Oils That Contain Ketones
Essential oils that have good amounts of ketones in them usually help in treating respiratory infections such as colds and flu. They are highly effective expectorants (promotes sputum secretion via air passages) & mucolytics (clears mucus from the airways).
Essential oils with ketones include:
6. Essential Oils That Contain Phenols
Essential oils that have phenols in them have anti-bacterial, antiseptic, rubefacient, disinfectant, and anti-infectious properties. However, you have to be cautious while using them, as prolonged usage leads to toxicity.
Essential oils with phenols include:
7. Essential Oils That Contain Aldehydes
Essential oils that contain aldehydes in them have sedative, anti-fungal, anti-inflammatory, antispasmodic, and anti-infectious properties. They are usually used for toning your nervous system and bringing your temperature down. These oils can irritate your skin to a great extent after they oxidize.
Essential oils with aldehydes include:
- Lemongrass oil
- Melissa oil
8. Essential Oils That Contain Ethers
Essential oils that have ethers in them usually have a refreshing, aromatic smell, similar to licorice or anise. They are well admired for their calming, carminative, and antispasmodic properties. They are generally used for reducing pain and spasms.
Essential oils with ethers include:
9. Essential Oils That Contain Esters
Essential oils that have esters in them are sedative and antispasmodic. They have calming, balancing, soothing, and uplifting properties. They are great for the skin and the digestive system.
Essential oils with esters include:
10. Essential Oils That Contain Oxides
Essential oils that have oxides in them are expectorant, antiviral, and mucolytic. They help in the treatment of respiratory problems and can stimulate your mental process.
Essential oils with oxides include:
Why Do Essential Oils Go Bad?
Every essential oil is volatile, and tend to oxidize. Any volatile substance will evaporate, and this is the reason you can smell its aroma. Every essential oil is made from various chemical compounds.
The lighter compounds are the most volatile and hence, they are the first to evaporate whereas the heavier compounds follow them eventually.
When an essential oil oxidizes, the sensitization risk also increases. So, applying it on the skin calls for a “health risk.”
Well, the lighter compounds are usually gentle on the skin. Therefore, when they evaporate, the leftovers are only the heavier ones. So, when you use it, you are at the risk of damaging your skin to a great extent. It can cause redness, swelling, and irritation.
An essential oil doesn’t necessarily “goes rancid” the way an expired ingredient does. You won’t see mold or something gross. You will notice that it no longer has that fresh “aroma” it once did.
It oxidizes, deteriorates, and loses its effectiveness after a while time. Hence, it shouldn’t be used once it is expired.
What Affects The Shelf Life Of Essential Oils?
The most common factors that affect the properties and shelf life of essential oils include:
The foremost and most common factor that alters the chemical structure of an essential oil is oxygen.
It easily reacts with other constituents and fades that “freshness” the bottle once used to have. Well, you won’t know the difference in the contents unless they are retested.
A research found that the monoterpene compounds in lemon oil decreased from 98% to 66.4% after 12 months of day-to-day air exposure. On the other hand, when this exposure is less – perhaps, once in a month, then the content degradation also minimizes.
But it is vital to understand that exposure to air doesn’t hasten the essential oil’s expiration. It only alters its composition, making it not that effective when it was initially opened.
Heat also affects an essential oil’s shelf life. But this factor has not been broadly studied. According to Robert Tisserand, an essential oil expert, essential oils should be kept away from heat. He recommends storing the oils in a cooler and darker space, ideally inside the refrigerator.
The reason is that heat causes the volatile components to evaporate much faster, but yes, for this to happen, the bottle’s lid needs to be removed. Based on what has been researched, the effects of heat on an essential oil varies depending on the compounds it contains.
For example, essential oils with compounds like citronellal, citral, or the ones that are fortified with more monoterpenes are affected by heat exposure to a great extent.
Moreover, an essential oil that is obtained using CO2 is more prone to deterioration from heat than the one that is not, though the exact reason isn’t known. (Source)
Light is another factor that promotes the growth of oxygen-free radicals. Now, these are very reactive and can modify the essential oils.
Say, for example, orange (sweet) oil, when exposed to UV rays, even for just 50 minutes causes dramatic changes. An ideal way to retain the oil’s composition is to store it properly. According to a study, fennel oil oxidizes faster when in light than stored in the dark.
Time also affects the shelf life of essential oils. Of course, if that little bottle isn’t exposed to light, heat, or oxygen (meaning that it is not opened in a cool, dark place), then it will be fine.
But the moment you open it, the process of deterioration begins and progresses with time. If you open the bottle regularly to use it, then the effect occurs more quickly.
However, there are a few essential oils, which gets better with time, just like wine. Patchouli oil is one among them. A few others include rose oil, sandalwood oil, cedarwood oil, vetiver oil, myrrh oil, and frankincense oil.
5. Chemical composition
Essential oils with higher alcohol content, particularly citrus oils, have a higher risk of expiring in 1-2 years. On the other hand, oils with heavier consistency, such as vetiver or patchouli, can last up to 5-6 years.
How To Tell If An Essential Oil Has Expired?
The following signs indicate that the essential oils have gone bad, and it is time to dispose them.
1. Aroma will not be fresh
If you smell the fragrance of essential oil after you buy it, the aroma is fresh. Familiarize with this scent so that you can know how it smells like when it goes bad.
2. Consistency changes
A majority of essential oils have the same consistency – fluid and smooth. If the oil has gone bad, it’s possible the consistency of the oil will thicken up. The oil can also take on a cloudy appearance, rather than the typical translucent coloration.
3. Sensitization increases
If you use an essential oil that has expired, you will experience redness and itching on the skin, besides being diluted. This happens only if it is very strong and its potency causes oversensitivity.
Look out for changes in the smell, color, and consistency. These are indicators that an essential oil has gone bad.
What Happens If You Use Expired Essential Oils?
Using expired or old essential oils is dangerous, especially when you apply them topically or consume them orally. When applied to the skin, they cause free radical damage to the skin cells and further causes them to age quicker. The skin can become wrinkled, saggy, and dull faster.
In addition, consuming expired oils can reduce your vitamin B & E levels. They also contain toxic compounds, which can lead to deadly problems like accelerated aging, cancer, and heart disease.
According to Dr. Andrew Weil, a holistic health sage, expired oils are “pro-inflammatory, toxic, and carcinogenic.”
How To Store Essential Oils?
The right storage methods can help in preserving the properties of essential oils. Make a note of these:
- Make sure that the lid of the bottle is tightly closed.
- Ensure that the essential oil is stored in a dark-colored bottle. This is to prevent direct sunlight. Usually, essential oils come packaged in amber glass. This is to protect them from quality degradation.
- The ideal temperature to store the essential oil is 36-40°F (or 2-4°C). The best way is to keep them in a refrigerator. But make sure you have a separate compartment for them. Obviously, you don’t want cross-contamination to happen between your food and essential oil (Nobody wants lavender-infused, leftover pizza! Plus, this can be harmful).
- Store the essential oils in small-sized containers to minimize oxidation.
- Keep the essential oils away from sunlight and heat.
- If you are not going to use the essential oil for a long time, perhaps, for a few months or you are going to be on vacation, then it is important to store the essential oils in the refrigerator.
- Never freeze the essential oils.
- Do not use dropper caps as lids because its rubber can contaminate the components, rotting your expensive oils in no time.