What Is Tamanu Oil and Can It Really Treat Acne Scars?

Another month, another new skin-care ingredient making the rounds on social media…. Tamanu oil is the latest trendy ingredient to take over TikTok, and (tongue twister aside) if you believe the hype, it boasts some impressive benefits.

Tamanu oil is relatively unknown in the United States when compared with the multitude of other powerhouse natural oils — jojoba, grapeseed, and tea tree, to name a few — found in beauty products. As with many plant-derived oils, tamanu has been used for centuries by the populations indigenous to the areas where it grows, including countries such as Mauritius, Samoa, and Malaysia; until now, though, modern-day skin-care formulators had yet to jump on the tamanu oil bandwagon. Fans of skin care and armchair beauty experts on TikTok are singing its praises as a miracle treatment for a broad range of issues, such as soothing rosacea and psoriasis and minimizing the appearance of acne scars.

But is there any scientific evidence to back up these lofty claims? We speak to dermatologists and cosmetic chemists to unpack the existing studies on this ingredient and get to the bottom of its purported skin-soothing, scar-healing abilities.

Meet the experts:

Ron Robinson is a cosmetic chemist and founder of skin-care brand BeautyStat.

Mona Gohara, MD, is a board-certified dermatologist based in Branford, Connecticut, and an associate professor of dermatology at Yale School of Medicine.

Krupa Koestline is a cosmetic chemist at KKT Innovation Labs.

Blair Murphy-Rose, MD, is a board-certified dermatologist specializing at the Laser and Skin Surgery Center of New York and a clinical instructor of dermatology at Weill Cornell Medical College.

What is tamanu oil?

Tamanu oil is extracted from nuts of the calophyllum inophyllum tree, an evergreen pantropical tree that is found in countries from East Africa to Southeast Asia, Oceania, and the South Pacific. Coincidentally, it is commonly referred to as the “beauty-leaf tree.”

Tamanu’s cold-pressed oil — dark green in color with a distinct nutty, earthy aroma — is extracted from seeds of the tree and has been used medicinally for centuries because of its antioxidant, antimicrobial, and anti-inflammatory properties, explains Ron Robinson, cosmetic chemist and founder of skin-care brand BeautyStat. The sap and mature fruit of the calophyllum inophyllum tree, however, can be poisonous to humans and animals if ingested — it was apparently crushed and used as rat poison at one time.

But tamanu oil, far from being toxic, is beneficial, thanks to its high fatty acid content, which aids in nourishing the skin, says cosmetic chemist Krupa Koestline. Explains Mona Gohara, MD, a board-certified dermatologist based in Branford, Connecticut, that also means tamanu is a fatty oil versus an essential oil. We’ll get into why that's important in a moment, but if you’re looking for the ingredient on an INCI list, you’ll recognize it as “calophyllum tacamahaca seed oil.”

Benefits of tamanu oil

The main claims being made about tamanu oil are that it’s anti-inflammatory, antimicrobial, antioxidant-rich, barrier repairing, and wound healing. Below, we’ll break down the legitimacy of each purported benefit, but it’s important to keep in mind that, at this time, none of the studies on tamanu oil have been conducted on humans or gone through double-blind placebo-controlled trials, which are the gold standard in the scientific community, says Dr. Gohara.

If a study is double-blind and placebo-controlled, it means neither the investigators nor the participants know who in the study received the placebo and who received the treatment. Until that sort of rigorous research into tamanu oil happens, Dr. Gohara says, we can't be 100% sure about its claims the same way we can about ingredients such as retinol and vitamin C.

Skin barrier repair

As mentioned, tamanu oil is rich in fatty acids that contribute to its skin-conditioning properties. But what makes tamanu oil stand out in the function of barrier repair is how those fatty acids — namely oleic acid, linoleic acid, and calophyllic acid — are all biosimilar to those in our skin, Dr. Gohara explains, which is a good thing in terms of hydration and barrier repair. “This is what I find most compelling about the ingredient,” she adds. It could also contribute to several of the ingredient’s other potential benefits.

Antibacterial properties

There have been several studies conducted that suggest tamanu oil could have significant antibacterial effects. According to Blair Murphy-Rose, MD, a board-certified dermatologist at the Laser and Skin Surgery Center of New York, a 2004 study found that tamanu oil exhibits high antibacterial activity against bacteria-involved wound infections. The same study also showed that tamanu oil may inhibit the growth of propionibacterium acnes and propionibacterium granulosum, two bacterium that are implicated with acne. This suggests potential use of tamanu oil as an acne treatment, but more research needs to be done to make a definitive conclusion before dermatologists prescribe it for any of their acne patients. Says Dr. Gohara, “There are so many other things that-are-tried and true for acne that work that I can't get behind recommending this as a substitute for one of those options without scientific backing.”

Anti-inflammatory properties

Historically, according to Koestline, people used tamanu oil to soothe sunburns and insect bites, apparently for good reason. Tamanu oil contains a molecule called calophyllolide, which, in a 1980 study, was found to possess possibly potent anti-inflammatory benefits. How does this help your skin? Says Koestline, “It may help reduce redness and inflammation associated with skin conditions like eczema and psoriasis.”

Wound healing

Tamanu oil’s potential anti-inflammatory benefits are the reason researchers have now turned their attention to its ability to heal wounds. “It’s believed to promote the formation of new tissue, making it popular for addressing scars, stretch marks, and minor skin irritations,” Koestline explains.

A 2017 study conducted on mice was the first to find that calophyllolide could be a good candidate for accelerating wound healing thanks to its anti-inflammatory effects, showing that the molecule sped up wound closures (specifically, in the epidermal and dermal layers of the skin) and led to an increase in collagen production.

Dr. Murphy-Rose points to a 2016 study that was conducted on human skin-cell cultures that investigated tamanu oil as a whole and its wound-healing properties, demonstrating “how it promotes wound healing in keratinocytes and fibroblast cells. In the study, tamanu oil-treated cells were found to heal faster than vitamin C-treated cells.”

Most recently, a 2021 study on rats compared tamanu oil with saline and centella asiatica (the stuff of cica creams) for their wound-healing potential. “On rats, wounds treated with tamanu oil healed better and showed higher collagen density,” says Koestline. “Although a similar study on human skin cells should be performed to better show its wound-healing properties.”

Antioxidant protection

Preliminary data suggests that tamanu oil might be an efficacious antioxidant and UV filter, potentially “helping protect the skin from UV damage, which might provide additional benefits to the skin,” says Robinson. (Of course, this would not take the place of your daily sunscreen.)

Does using tamanu oil help with acne scars?

The research is still very limited, but the initial data showing tamanu oil’s ability to reduce inflammation, heal wounds, and promote collagen and glycosaminoglycan production (the latter of which is a water-binding molecule that provides moisture to the skin and keeps collagen and elastin in good condition) means that it may have the ability to reduce the appearance of fresh post-acne marks, which Dr. Gohara notes are different from existing, long-formed scars. “A mark is something transient and left behind after a pimple. A scar is something that’s permanent,” she explains. “Scarring is going to require something procedural to treat, but for a marking — maybe because [tamanu oil] has these antioxidant and barrier repair properties — maybe it can help to even out the skin tone a bit. But reducing a true, permanent scar? No, not happening.”

Dr. Murphy-Rose echoes this: “True acne scarring can be challenging to treat and typically responds best to in-office devices. Still, tamanu oil is believed to aid in wound healing and may work well in conjunction with other scar treatments,” she says, adding that if a patient has acne, she would advise against using a facial oil regardless of its purported benefits.

Risks of using tamanu oil

If you don’t have a nut allergy, sensitive skin, or a skin condition, then there is little risk for adding tamanu oil to your routine. As usual, though, we recommend patch-testing on your forearm any new product you try and waiting a day or two to see if you develop a reaction.

People who have nut allergies should avoid tamanu oil because it's derived from a tree nut. And while many of the voices on TikTok have vouched for the ingredient as a treatment for rosacea, psoriasis, and eczema, Dr. Gohara strongly advises anyone with any sort of skin sensitivity — eczema, rosacea, perioral dermatitis proclivity, psoriasis, for example — to steer clear of it because it’s a nut oil and can therefore be a bit more sensitizing than other skin-care oils.

Is tamanu oil comedogenic?

At this point we don’t have enough information to determine if tamanu oil is comedogenic or not, which means consumers should use care, advises Robinson.

Dr. Murphy-Rose believes it likely has the potential to clog pores, as is the case with many oil-based products. Dr. Gohara reminds us, however, that nothing has to be comedogenic if applied in small amounts. “Anything that contains oils or fatty acids or has a barrier repair function — even an ingredient as highly touted and recommended as ceramides — is going to be too hydrating and comedogenic when overused,” she says. “As long as those types of products are applied in small amounts, they have potential to be noncomedogenic.”

If you’re interested in incorporating tamanu oil into your routine but worried it might clog your pores, consider introducing the ingredient into your regimen slowly. Start with one or two days a week, once a day, and see how you fare. If you don’t break out, it means you can apply it more frequently.

How to use tamanu oil

Tamanu oil is most often found in its original form, as an oil, on its own or combined with other fatty and/or essential oils. However, it can also be mixed into serums, creams, and lotions for the skin and hair, says Dr. Murphy-Rose. Incorporating tamanu oil into your routine requires you answer two simple questions: Where do you want to use it (face or body)? And, depending on which area you choose, are you a fan of using pure oils? If the answer to the second question is no, you’ll want to look for a cream, lotion, or serum that includes tamanu oil on its ingredients list.

When tamanu oil is incorporated into a formula — like the Kiehl's Daily Reviving Concentrate or Shea Moisture Tamanu Oil & Shea Butter Lotion — just follow the rules of application order for any serum or cream. But if you're interested in trying pure tamanu oil, the best way to use it is as an occlusive layer over your moisturizer, which creates a protective barrier on the skin. This way, moisture is locked into the skin while simultaneously drawing in moisture from its surroundings, explains Dr. Gohara.

A final word

If we had to give tamanu oil a skin-care report card, it would receive an evaluation of “shows promise.” The research that’s out there, albeit limited, shows that there might be some merit to what people are saying on TikTok about the ingredient, but until we have more information, we can’t say for sure. “It's fair to say that it may have anti-inflammatory properties and it's possible that it has antibacterial properties,” says Dr. Gohara. “We live in a world of Western medicine, but Eastern medicine is legit. There are so many plants that are medicinal. I don’t want to diss tamanu oil — it might be legit; I just want to see the science behind it first.”