Eucalyptus: It Smells Good, But Does It Actually Heal?
Nothing transports us in our minds with such acuity as the sense of smell.
I was en route to the rural Indian mountain town of Shimla in Himachal Pradesh, known for its diversity. Culturally, the countries of Pakistan, China and Nepal all seem to converge on this small finger of India that pushes northward. Geographically, the foothills of the Himalayas push down on lush forests as a haven of sustenance and protection for wildlife.
After a white knuckle bus ride through the narrow mountain road to Shimla, I emerged eager to hike and take in all the offerings of this remote place.
What met me was most unexpected.
Carried on the wind that swept up the Himalayas and through the endless stands of vegetation was an overcoming aroma that transported me subconsciously to my childhood bedroom on Ramsdell Street. It was eucalyptus, the intense and ubiquitous remedy for the myriad of cold viruses I encountered growing up in mom's little green jar.
As I looked up and saw monkeys playing on the tall thin trees with green, waxy leaves I felt healthy and clean. Who could mistake the smell of eucalyptus and its message for our senses?
This blog will highlight the science and medicinal use of eucalyptus.
Over 700 species of eucalyptus are known, most of which are native to Australia. The many species can range from small shrubs to towering trees. Most all eucalyptus are evergreen, keeping their green, waxy leaves year-round. Both flowers and fruit are produced by the eucalyptus. The flowers appear as numerous white or red puffs and the fruit, known as gumnuts, have the appearance of a small capsule. Bark of the eucalyptus varies with species from thin fibers to thick and rough. Eucalyptus trees are presently cultivated in temperate and tropical climates beyond Australia for their various desirable attributes.
Non-Medicinal Uses for Eucalyptus
Beyond medicinal application, eucalyptus trees are used as a source of wood because of their rapid rate of growth. Because of their water-guzzling ability, public health initiatives have incorporated eucalyptus trees in their efforts to eradicate malaria. Planting eucalyptus reduces standing water in swampy areas where mosquitos like to breed.
Some environmentalists, however, are critical of the drastic environmental changes that these "foreigners" can bring. Eucalyptus oil is used in many cleaning products and as a natural insecticide. The oil is readily distilled from the distinctly fragrant eucalyptus leaves.
Medical Uses for Eucalyptus
- Anti-Inflammatory + Anti-Microbial (And Antifungal?): While the health benefits have not been hands-down scientifically proven, eucalyptus oil is generally felt to have anti-inflammatory and antimicrobial properties.Some evidence suggests that there may be antifungal properties as well.
- Immunity Boost: A small lab-based study did determine that eucalyptus oil stimulated the action of human macrophages, important in our immune response to allergy and infection.
- Reduced Need for Steroids in Asthmatics: Most medicinal uses with eucalyptus are applied to the respiratory system. A couple studies have documented benefit, one in asthmatics on chronic steroid use and the other in respiratory infections. In the placebo controlled asthma study, subjects were able to reduce the amount of anti-inflammatory steroids required to control asthma symptoms when eucalyptus oil was used compared to placebo.
- Fights Bacteria in the Lungs: In the later study, use of eucalyptus oil showed reduced bacterial prevalence in respiratory cultures compared with those not exposed to eucalyptus.
- Prevents Infection in Wounds: The ant-inflammatory and antimicrobial properties can also be used on skin injuries such as cuts and scrapes.
Eucalyptus oil is first diluted then and applied to skin, inhaled as aromatherapy or ingested. Commercially available ointments are already diluted. Essential oils must be diluted.
- Dilute Appropriately: It is important to note that non-diluted eucalyptus oil can be toxic and even fatal if enough is ingested. It is important to dilute the oil accordingly before use.
- Test for Allergy: Allergy to eucalyptus has rarely complicated its use and a small application to the skin for several hours should first be performed as a precaution.
- Hasn't Been Proven Safe for Pregnant or Nursing Mothers: For this reason, eucalyptus oil is not recommended for use in pregnant or nursing individuals.
- Not All Eucalyptus Oils Are Created Equally: It is felt by experts on essential oils that different species bring different results in their medicinal properties.
The smell of eucalyptus conjures a sense of cleanliness and clear respiratory passages. Native to Australia, it is now widely found in warmer climates. The medicinal use of eucalyptus is widely accepted, but not definitively proven in regards to anti-inflammatory and anti-microbial properties. It's oil can be applied or ingested, and its aroma can be inhaled. Cautions must be used, however, that this potent compound is appropriately diluted.
Clinical Advisor, October 2012