Most readers have probably never seen a eucalyptus tree, or enjoyed the fresh, pine-like scent of a grove of eucalypts. (Yes, that’s really the plural of eucalyptus.)
The telltale, camphoraceous aroma of eucalyptus may be quite familiar anyway, however. The oil from these trees is commonly found in products like vapor rub and mouthwash, and even in some chewing gums. It’s also often used as an insect repellent, so those who have annual mosquito invasions may associate the smell of eucalyptus with muggy summer nights – and itchy bug bites.
Readers who are into aromatherapy are likely to think of eucalyptus in a very different way. The essential oil from this tree isn’t just used for its strong decongestant properties or its ability to convince insects to leave you alone; it’s often employed for its more general – and impressive – apparent long-term health and wellness benefits.
Let’s learn more about this oil with a unique aroma and a lot of devoted fans.
The Versatile Eucalyptus Tree
Eucalyptus trees need a temperate climate without frost to flourish. That’s why they grow throughout the southern regions of California, Texas and Florida, as well as Hawaii and parts of the southeastern and southwestern United States. They’re definitely not native to America, though.
There are more than 800 known species of eucalyptus, and almost all of them originally came from Australia. In fact, about three-quarters of all forests on that continent are primarily eucalyptus forests.
Eucalypts can grow as tall as 400 feet with a circumference that can reach 24 feet, although some species do grow as dwarfs. They usually top off at 160 feet in non-native environments, with about half of that growth seen in their first 10 years. In most eucalypts, dead bark accumulates over the years and eventually drops off.
The first recorded botanical collections of eucalyptus were taken from Australia to Britain in the late 16th century, during the expeditions of Captain James Cook. But it wasn’t until the California Gold Rush that the trees were introduced to America; Australians seeking their fortunes brought packages of Tasmanian Blue Gum (eucalyptus globulus) eucalyptus seeds with them.
After eucalypts began sprouting, the evergreens were quickly planted throughout the state with the encouragement of California’s government. They were used as windbreakers and as a source of wood, but also to provide variety to the state’s landscape. Officials viewed the blue gum tree as a more promising alternative to oak trees.
That didn’t go as planned. Blue gum eucalyptus wood wasn’t suitable for most construction and woodworking purposes (less-common red gum eucalyptus trees produce better wood). It was really only usable as firewood. And the trees grew so quickly and so high that they used up local water supplies. Even so, after the U.S. government predicted an early 20th century timber famine, speculators invested in newly-planted, huge eucalyptus plantations; the trees were seen as a second potential gold mine, since they grew so large and so quickly.
There was no timber famine, but the eucalypts kept growing. They weren’t compatible with native vegetation, they didn’t support local wildlife as well as native trees and plants, and they weren’t great for building. California now characterizes the eucalyptus as an “invasive species.”
There was one other problem, too: eucalypts catch fire easily. Needless to say, that’s a huge issue in states like California which suffer with frequent wildfires. Many local officials have called for the removal of thousands of eucalyptus trees for that reason, although there’s some debate over whether eucalypts are any more of a hazard than native vegetation.
Either way, the eucalyptus tree is in America to stay. It’s hardy (in the areas where it grows well) and it spreads easily, which is obvious from its proliferation throughout the country’s sub-tropical areas.
So what else it good for? You know where we’re going here: essential oil sourced from eucalyptus has become a major justification for the cultivation of eucalypts.
What Is Eucalyptus Oil?
The tree contains a large amount of essential oil, which is steam distilled from eucalyptus leaves. The active ingredient in eucalyptus oil is known as eucalyptol (1,8-Cineole), and since the essential oil contains more than 65% eucalyptol, a little can go a long way.
Of course, steam distillation wasn’t available when eucalyptus oil was first used as a medical treatment. Australia’s native peoples reportedly boiled eucalyptus leaves to produce oil many centuries ago for use as an antiseptic, and the first recorded medicinal use of eucalyptus was on board British ships, around the time the first Australian settlements were created.
In the mid-1800s, German-Australian botanist Ferdinand von Muller took a big interest in the antiseptic possibilities of the blue gum eucalyptus, and helped introduce the tree to Europe, Africa and the Americas for that purpose.
Later in that century, the man who pioneered the technique of antiseptic surgery, Joseph Lister, publicly advocated for the use of lavender oil in healthcare settings as a disinfectant and wound treatment. It was widely used to clean catheters during that time, and was studied extensively for a while. But the development of new treatments (including antibiotics) superseded medical use of the oil during most of the 20th century.
The medical use of eucalyptus oil may have been on hold for a while, but its ability to act as a natural pesticide was recognized during this period, and later research showed the scientific reasons for the oil’s effectiveness as an insect repellent. Eucalyptus was first registered as an insecticide in 1948.
Eucalyptus oil became a popular disinfecting agent in cleaning products, and after it was found to be safe for humans in small amounts, was blended into products like vapor rub because of its soothing and cool vapor. It later was added to cough drops, lozenges, inhalants and mouthwash because it was found to act as a decongestant.
However, its most promising use is as an essential oil for topical application and in aromatherapy – because of the many medicinal benefits it appears to provide.
Medical Benefits of Eucalyptus Essential Oil
The possibilities of eucalyptus oil as a disinfectant and decongestant were first identified by anecdotal evidence and observations. Those abilities have since been confirmed through extensive research, which continues today.
Here are some of the many ways that eucalyptus essential oil has been shown to provide medicinal and health benefits.
Disinfectant and Antibiotic Properties
Eucalyptus oil’s long history of use as a disinfectant was an obvious topic for researchers to study first. Studies show that the oil has strong antimicrobial properties and may be a suitable replacement for prescription antibiotics. And it’s been found that the oil, when combined with other substances like alcohol, is able effectively remove difficult-to-kill bacteria and viruses like MRSA, E. coli and Candida albicans from surfaces in health care facilities.
Decongestant, Anti-Inflammatory and Respiratory Relief Properties
It’s not surprising that eucalyptus is still a key ingredient in topical decongestant products like VapoRub. One study examined the combination of eucalyptus oil, camphor and menthol, and found that it was effective at treating congestion, cough and sleep problems in children.
A review of research looked specifically at eucalyptus essential oil, finding that inhaling the oil appeared to be a potent treatment for infections of the sinuses and respiratory tract. And research showed that cineole, the active ingredient in eucalyptus oil, was able to significantly reduce the effects of bronchitis in just four days.
Much of eucalyptus oil’s power to treat respiratory issues is credited to its anti-inflammatory properties, which are able to reduce the airway inflammation that causes so many respiratory conditions. In that vein, some studies have also shown that cineole may also be effective as an asthma treatment, although not all research confirms those findings.
Pain Relieving Properties
Research suggests that topical pain rubs containing eucalyptus oil work for good reasons. One study highlighted the positive physical reactions produced by a eucalyptus-containing rub, including increased blood flow and lowered skin temperature. Another looked at inhalation of eucalyptus essential oil by knee surgery patients, and found that pain levels and blood pressure were significantly reduced after a dose of the essential oil. Research on the relationship between eucalyptus oil and pain continues.
Other Properties of Eucalyptus Essential Oil
- Immune System Support: A survey of research into various essential oils has concluded that two of them, ginger and eucalyptus essential oils, appear to have substantial ability to enhance immune system function.
- Tooth and Gum Health: It may have sounded strange when we earlier mentioned that eucalyptus oil can be found in mouthwash and chewing gum, but studies have shown that the essential oil apparently enhances periodontal health, apparently due to its antibacterial properties.
- Headache Relief: The use of eucalyptus oil to relieve pain appears to be particularly effective against migraine headaches, when the oil is paired with peppermint oil and applied topically to the forehead.
- Anxiety: Eucalyptus isn’t one of the essential oils most commonly recommended for anxiety and stress relief (lavender is usually the favorite), but there are indications that eucalyptus oil can help. One study found that inhalation of the oil before outpatient surgical procedures significantly reduced patients’ anxiety.
You’ve certainly noticed that the different ways to realize the medical benefits of essential oils include both inhalation and topical administration. They’re important, but not the only ways you can use eucalyptus oil.
How to Use Eucalyptus Essential Oil
The easiest way to receive some of the benefits of eucalyptus oil is to use one of the products containing it; vapor rubs, ointments and creams, lozenges and sprays, bath products and oral hygiene products are just some of them.
Those products, however, all contain other ingredients as well, meaning you won’t get as much eucalyptus oil – or as many of the benefits – as you would get by using the essential oil by itself.
- In an essential oil diffuser: Many people use this oil by placing a few drops of eucalyptus oil into an aromatherapy diffuser. Don’t own a diffuser? You can put it into a humidifier, or just place a few drops of oil and some water into a spray bottle and spray it around the room.Some find the scent invigorating while others find it relaxing, but the aroma is certainly one which will infuse the air with a noticeable and (at least for most people) pleasant scent. A number of the medicinal benefits of eucalyptus essential oil can also be realized when it’s inhaled in ambient air.
- Inhaling it: When you’re trying to relieve congestion or respiratory distress, you’ll get more relief from a homemade “eucalyptus essential oil inhaler” than you will from a commercial product that contains eucalyptus oil. Simply add a few drops of the oil (or some eucalyptus leaves) to a vaporizer or a container of hot water, and inhale the vapor deeply for 5-10 minutes.Another way to do it is to put a few drops of the essential oil into a towel or washcloth and take it into a hot shower with you. The steam from the heated cloth makes a perfect mini-inhaler. If you’re on the go, you can even put a few drops into a handkerchief and inhale the aroma that way.
- Applied topically: You shouldn’t use undiluted eucalyptus essential oil on your skin. Otherwise, it can cause burns, irritation or itching. (The same is true for most essential oils.) After dilution in a carrier oil like coconut oil or jojoba oil, using one part essential oil to nine parts carrier oil, the solution can be used for massages, applied directly to wounds or sores, or rubbed into sore or aching muscles. You can also mix the oil with petroleum jelly for a muscle rub.
- Taken internally: The best medical advice is not to consume eucalyptus oil because it can be poisonous; as little as a teaspoon has been fatal to some people. Some naturopaths and aromatherapists do suggest it though, so if you do plan to take the oil internally, always dilute it in warm water and take no more than 0.05 milliliters. Use medicine droppers to be sure of the amount. Even better, don’t do it.
- Make your own cleanser: To take advantage of eucalyptus oil’s disinfection abilities, just mix ¼ cup of white vinegar with 1¾ cup of water and then add ten drops each of eucalyptus, wild orange and peppermint oil. Used in a spray jar, it can clean and disinfect just about any surface in your home. It smells wonderful, too.
You can also experiment with homemade essential oil blends with other EOs like tea tree, lavender, marjoram and cedarwood oils; they provide even more health benefits and different but pleasant scents. For variety, you can also try essential oils extracted from other species of the eucalyptus plant, like narrow-leaved peppermint (eucalyptus radiata) or lemon eucalyptus; each has a different scent (which should be obvious from their names) than blue gum eucalyptus.
What Else You Should Know About Eucalyptus Essential Oil
To get the greatest benefit from eucalyptus oil, purchase high-quality, pure essential oil from a reputable producer – and keep it in an amber- or cobalt-colored glass bottles, stored away from heat and light. Closed bathroom cabinets, kitchen cabinets or kitchen pantries are ideal.
You already know from the previous section that undiluted eucalyptus essential oil can cause side effects like skin irritation and burns, and serious illness or death when consumed internally. Always make sure your oils are always kept out of the reach of children. Eucalyptus oil is also highly allergenic, so it might be a good idea to take an allergy test before trying it.
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