22 June 2022
When it comes to essential oils, no other than tea tree oil enjoys a mythical status. Long regarded as a hero that calms the skin, cures acne and treats infection, tea tree oil’s multitasking benefits are not lost on skincare fans. Should we start embracing tea tree oil into our skincare routine? Here’s a look at the science and data behind this popular essential oil- before jumping on the trend.
Tea tree oil is a type of essential oil obtained from the steam distillation of Melaleuca alternifolia, a plant native to Australia. Historically, Aboriginal Australians have used tea tree oil for healing of various ailments- Crushed leaves of the Melaleuca alternifolia tree were sprinkled on wounds; or inhaled to treat coughs; and soaked tea tree leaves were used for treating sore throats.
These benefits of tea tree oil have prevailed and today, you’ll find that tea tree oil is a popular, multi-purpose cure-all remedy used for a host of ailments such as wounds, acne, hypersensitivity and infections.
Is tea tree oil really the wonder ingredient that it seems to be? Here’s a look at the data and science of tea tree oil in dermatology.
Tea tree oil contains more than 100 components that confer its antimicrobial, anti-inflammatory and antioxidant effects. The two major components of tea tree oil are terpinen-4-ol and 1,8-cineole. Terpinen-4-ol is the active ingredient that confers tea tree oil its antimicrobial and anti-inflammatory benefits. On the other hand, 1,8-cineole is an allergen.
Tea tree oil formulations have been regarded as a popular, ‘natural’ remedy for a myriad of dermatological conditions including acne, fungal infections including dandruff, hypersensitivity and wound healing. Despite its popularity,the benefits of tea tree oil are mostly anecdotal. Research into tea tree oil is spotty and good quality, randomised controlled trials that assess the effectiveness of tea tree oils are lacking. Here’s what the research on tea tree oil shows:
Tea tree oil for acne
One of the most popular natural remedies for acne is tea tree oil. A cursory glance at the drug shore will reveal a plethora of tea tree oil products that promise to cure all forms of acne.
Acne or pimples is a multi-step inflammatory disease of the pilosebaceous glands. Some of the processes involve hyperkeratinisation and inflammation by the C. acnes bacteria and inflammation. Treatments and skincare for acne like retinoids involve addressing these key steps. The antimicrobial and anti-inflammatory benefits of tea tree oil form the cornerstone for its role in acne skincare.
Despite the hype and popularity of tea tree oil for reducing acne, the anti-inflammatory and antimicrobial benefits have mostly only been demonstrated in in-vitro studies. There are a few small studies in humans that have shown that 5% tea tree oil can reduce acne; but effects of tea tree oil were slower than other over counter actives such as benzoyl peroxide. In 2016, a Cochrane review of complementary acne treatments such as tea tree oil concluded that there is a lack of evidence to support the use of these options for treatment of acne vulgaris.
Tea tree oil for fungal infections and dandruff
Tea tree has also been used as a form of antiseptic and remedy for fungal infection in traditional medicine. In more recent times, the research for tea tree oil’s antifungal effects have been focused mostly on the Candida species of fungi.
Tea tree oil owes its fungicidal properties to one of its active ingredients, terpinen-4-ol. Terpinen-4-ol disrupts the cell membranes of fungi and impairs the ability of fungal cells to use oxygen, ultimately leading to their death. In a few studies, tea tree oil used at 5% concentration has been shown to improve fungal infections in the nails. However, the mechanisms of workings for tea tree oil have not been reliably proven; and validation in large human trials are also lacking. Fungal infections can be difficult to treat and can spread if not treated properly. Hence, tea tree oil is seldom recommended by doctors as first line treatment for fungal infections. Instead, anti-fungal and anti-inflammatory ingredients remain as first line management for fungal infections.
Dandruff is a fairly common condition of the scalp. It is characterised by white, dry flakes of skin on the scalp and itching. Dandruff has been linked to skin colonisation by a type of yeast called Malassezia furfur and the subsequent inflammatory response.
A few studies suggest that using shampoos containing tea tree oil can help to improve mild to moderate dandruff, compared to placebos. However, for more severe or stubborn cases of dandruff, it’s best to seek a doctor’s consultation- anti-fungal shampoos and medications will be needed to successfully treat dandruff.
Tea tree oil for wound healing
Another popular use for tea tree oil- wound healing. Despite its popularity, scientific data for accelerating the stages of wound healing or reducing scars is very scarce. Tea tree oil may benefit superficial wounds for another reason- to prevent wound infections.
In traditional medicine, tea tree oil was also used to treat wound infections. Based on in-vitro studies, terpinen-4-ol in tea tree oil offers some antibacterial advantage against common types of bacteria by disrupting the bacteria membranes, based on in-vitro studies. Studies on tea tree oil’s antimicrobial effects in humans are few and inadequate. Instead, for a wound infection, seek your doctor’s advice for proper care. A wound of any kind can potentially be complicated by infections, prolonged healing and scarring. Treatment guidelines often recommend conventional medications and treatments which have more robust data and trials to support their use for wound healing and infections.
For ‘clean’, ‘green’ or ‘natural’ beauty fans in favour of plant based ingredients- here’s a head’s up- it’s not any safer than ingredients that are not derived from plants. The greenwashing deception deserves a blogpost on its own; but essentially plant oils such as tea tree oils have a higher propensity to cause allergic reactions than ingredients that were synthesised.
Tea tree oil has one of the highest rates of allergic contact dermatitis, compared to other essential oils. Allergic contact dermatitis results in red, itchy rashes on the skin. If you have a condition where the skin barrier is compromised; such as eczema, it’s best to avoid using tea tree oil until the flare has resolved and the skin barrier is normalised.
If you are unsure of how your skin may react with tea tree oil; start with a product that contains a lower concentration of tea tree oil; or do a patch test on your skin. Another helpful tip- use a fresh batch of tea tree oil. The ingredients in tea tree oil can oxidise over time; and the byproducts of oxidation can also worsen allergic contact dermatitis. To avoid using oxidised tea tree oil; store your products in dark and airtight packaging and use the product within the recommended time frame. If it’s expired, it’s time to bin it.
Tea tree oil is also toxic when ingested, so remember to keep it out of reach of your children!
Tea tree oil in skincare has its roots in traditional aboriginal medicine for multiple conditions. However, support for tea tree oil’s benefits are at best anecdotal; research is still inconclusive for doctors to recommend this oil for conditions like acne and skin infections.
Using tea tree oil is also not without its side effects. The risks of developing allergic contact dermatitis from using tea tree oil is higher compared to most other essential oils. Tea tree oil is also toxic when consumed, so remember to keep it away from children!
1. Melaleuca alternifolia (Tea Tree) Oil: a Review of Antimicrobial and Other Medicinal Properties. Carson et al. Clin Microbiol Rev. 2006 Jan; 19(1): 50–62.
2. A review of applications of tea tree oil in dermatology. Payzar et al. Int J Dermatol. 2013 Jul;52(7):784-90.
3. Tea tree oil: contact allergy and chemical composition. Groot and Schmidt. Contact Dermatitis. 2016 Sep;75(3):12-43.