Ti-Tree essential oil is often praised for its anti-microbic properties, particularly as an anti-bacterial agent. It’s recommended for everything from acne to first-aid. But what’s the science behind it? I wanted to find out, so I did some digging on the research studies that have been done. Below I have summarized a few different studies and their results, with included links below.

To start off, let’s talk about what exactly Ti-Tree essential oil is. This oil comes from the Myrtaceae family and its botanical name is Melaleuca alternifolia. It is traditionally harvested from Australia, but many other countries, such as China, have started production. The main chemical constituents that make up Ti-Tree are:

• Monoterpenes (35-70%) – y-terpene (9-29%) a-pinene (3%), a-terpinenes (8-10%), cymene,
• Sesquiterpenes (8-22%) – a-phelladrene (1-2%), b-caryophellene (1-2%), aromdrene (3-7%)
• Alcohols : Monoterpenic (45-55%): terpineol (25%), a-terpineol (3.5%)
• Oxides : 1-8 cineole (2-15%)

As you can see, this oil has a varied list of very useful chemicals to help with many bacterial, viral and fungal infections.

No one seems to be able to agree on how to spell Ti-Tree, so you may see these spellings with/without hyphens included: T Tree, Tea Tree, Ti Tree

Ti-Tree is very potent and should be used in low concentrations as it may irritate skin. Like all essential oils, you should not use it on the skin full strength, always diluting in appropriate carriers before use.  We do not recommend using any essential oils for internal use.  If pregnant or suffering from serious medical conditions, consult a qualified health professional, experienced in the use of essential oils.

Ti-Tree has a lot of research behind it and has been included in countless scientific research studies. Here are a few of the studies summarized:

Acne: 

Multiple studies have been conducted that establish Ti-Tree’s effectiveness in treating acne (clinically known as acne vulgaris). Following are a few notable investigations:

1. Study Size and Method: This first study(1) was done with 60 patients who had mild to moderate acne. They were randomly divided into groups and given either a Ti-Tree gel or a placebo. They were examined every 15 days for a period of 45 days total. Their acne was measured by counting the number of lesions they had, and by using the acne severity index (known as ASI).

The results: The researchers found that the Ti-Tree gel was 3.55 times more effective in reducing the total number of lesions and 5.75 times more effective in improving participant’s ASI score.

2. Study Size and Method: This study(2) was done with 124 randomized participants that had acne. Participants were either given 5% ti-tree in a gel formulation or 5% benzoyl peroxide lotion. They measured the results by the amount of inflamed and non-inflamed pimples.

The results: This study found both Ti-Tree and benzoyl peroxide lotion to be effective in reducing acne, and while the Ti-Tree did work slower, there were fewer side effects than with the benzoyl peroxide application.

Wound healing and bacterial infection:

Study size and method: A study(3) was done with 32 participants that had Methicillin-resistant Staphylococcus aureus – a bacteria infection that interferes with wound healing. All the participants had chronic wounds that had existed for 6+ weeks and contained MRSA bacteria. The participants were randomly assigned to either the testing group or the control group. Those in the testing group where given a topical treatment of 10% ti-tree essential oil diluted in a carrier oil. The wound was then dressed with a non-adhesive pad. 

“Wound measurements were obtained by first tracing the wound and then calculating the wound healing condition using the Pressure Ulcer Scale for Healing (PUSH) tool 3.0, where surface area (wound size), exudate, and type of wound tissue are assigned different sub-scores ranging from 0 to 4. A comparison of total scores by adding together these sub-scores measured over time provides an indication of the improvement or deterioration in wound healing. A score of 0 out of 16 is an indicator of a completely healed wound. In total, five measurements were performed on all participants: before the implementation of wound dressing, the 1st week after the implementation of wound dressing, the 2nd week…, the 3rd week…, and the 4th week after the implementation of wound dressing.” (2014).

Wound samples were also taken and tested for MRSA bacteria. Samples were taken 5 times: Once before the study and afterwards at 4 one-week intervals.

The results: In the test group there were no allergic or adverse reactions. The researchers found that after the four week study, the wounds for all of the testing group had completely healed. They all had PUSH scores of 0. In comparison, the control group had a mean PUSH score of 4.6 by the end of the study. The MRSA bacteria levels significantly decreased for the testing group after the four week period. The bacteria was completely eliminated in 14 out of the 16 participants.

Antiviral Activity:

1. Study Method: This study(4) tested how effective Ti-Tree is against Herpes virus. To do this, the researchers incubated Herpes virus samples with different concentrations of Ti-Tree Oil, then used those treated viruses to infect cells. After four days, the amount of plaque formed by the treated viruses compared to the control group was measured.

The Results: Plaque formation of Herpes Virus 1 and Herpes Virus 2 were reduced by 98.2% and 93.0% with concentrations of Ti-Tree oil that does not directly kill cells, and instead affects cell transport. This study also measured the effects of Eucalyptus Globulus oil using the same method, and found a 57.9% reduction for Herpes Virus 1 and a 74.5% reduction for Herpes Virus 2.

Tobacco Mosaic Disease – Photo from Washington State University

2. Study Method: To test the antiviral affects of Ti-Tree, this study (5) sprayed Tobacco plants with different concentrations of Ti-Tree oil, and had a separate control group of plants. They then infected the plants with Tobacco Mosaic virus, a RNA virus that causes discoloration in plant leaves and ‘mosaic like’ mottling. After ten days, they measured the lesions per square centimeter on the plant leaves.

The results: After the ten days, the plants sprayed with Ti-Tree Oil was found to have ‘significantly less’ lesions per square centimeter than the control group.

Conclusion:

Ti-Tree has shown in multiple studies that it is effective in fighting different forms of bacteria, viruses and infections. There is a large amount of research about Ti-Tree that I’d highly recommend looking into if you are interested in learning more.

Sources for further reading:

1. The efficacy of 5% topical tea tree oil gel in mild to moderate acne vulgaris: a randomized, double-blind placebo-controlled study. by Enshaieh S, Jooya A, Siadat AH, Iraji F. (2007) https://www.ncbi.nlm.nih.gov/pubmed/17314442
2. A comparative study of tea-tree oil versus benzoyl peroxide in the treatment of acne. by Bassett IB, Pannowitz DL, Barnetson RS (1990). https://www.ncbi.nlm.nih.gov/pubmed/2145499
3. A randomized controlled trial of topical tea tree preparation for MRSA colonized wounds by Rainbow L.P.Leea, Polly H.M.Leung, Thomas K.S.Wong (2014) https://www.sciencedirect.com/science/article/pii/S2352013214000027?via%3Dihub
4. Antiviral activity of Australian tea tree oil and eucalyptus oil against herpes simplex virus in cell culture by Schnitzler P, Schön K, Reichling J  (2001) https://pubmed.ncbi.nlm.nih.gov/11338678/
5. Antiviral Activity of the Essential Oil of Melaleuca alternifolia (Maiden amp; Betche) Cheel (Tea Tree) Against Tobacco Mosaic Virus by Chris D. Bishop, Journal of Essential Oil Research (1995) https://www.tandfonline.com/doi/abs/10.1080/10412905.1995.9700519
6. Melaleuca alternifolia (Tea Tree) oil: a review of antimicrobial and other medicinal properties by Carson CF, Hammer KA, Riley TV. (2006) https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1360273/