For some reason, at HBS we end up spending a lot of time fact checking claim about oils. While it's mostly "hot topics" like CBD oil, MCT oil or fish oil, today we take a different, slightly weirder path.
The flightless emu bird (Dromaius novaehallandiae), native to Australia, is probably best known for being on Australia’s coat-of-arms, opposite the kangaroo. Emu oil is a well-known, commercially available product, notably in countries such as Australia and the United States, and believed to have many therapeutic and medicinal properties.
Being from Australia myself, I often come across tubs of emu oil-based creams and lotions marketed for their skin moisturising and cosmetic properties. Other claims include that it reduces inflammation, lowers cholesterol and gives you wonderful hair and nails!
What Is Emu Oil?
Historically, Australia’s indigenous Aboriginal population and, later, the white settlers to Australia topically applied the emus liquid fat to, anecdotally, treat various ailments such as wounds, to alleviate pain and inflammation, and for musculoskeletal disorders.(1) It is now farmed in many countries, such as America, Australia and India, mainly for its prized oil, and commercial emu-breeding has become a multi-billion dollar industry since the 1990’s (5).
Emu oil is extracted from its fat deposits. An adult emu weighs about 45 kg, of which about 10 kg is body fat. Stored on the emus back, it is known as the ‘back pad’. (2) Bright yellow in color (3), emu oil has an extremely high fatty-acid (FA) composition. Monounsaturated FA (MUFA) makes up over half (53%) of the FA component of emu oil, about a third is saturated (32.5%), and the polyunsaturated FA (PUFA) component is almost 11%.
It also contains some unsaturated FAs, like linoleic acid. (6) The non-fat component, which is very small in comparison, includes various compounds like antioxidants, notably carotenoids, flavones, polyphenols, and phospholipids.
It’s thought to be a great supplement as it contains all three of the omega FA’s (ie. omega-9, omega-6 and omega-3). (6) Its largest omega-FA component is oleic acid (49%), an omega-9 MUFA. (6)
However, the FA composition of emu oil can vary! It is highly dependent on the bird’s diet, the method of oil extraction, and the type of fat tissue from which the oil is extracted. (4, 5) Rat studies have shown “considerable variability in the potency of some commercial oil samples” and highlighted “the need for greater quality control in the manufacture of emu oil products”. (1) So, in essence, the quality of the emu oil product is an unknown.
Is There Any Research?
Research specifically in to emu oil, per se, is not extensive, at this point in time. A PubMed search yields the following results, in the English language: 41 total papers, of which only 10 involve human species. There are no powerful meta-analysis (MA), nor systematic review (SR), papers and 3 are fairly recent reviews on the topic of emu oil.
However, research on the individual components found in emu oil is much more extensive. FA research has over forty-thousand PubMed indexed papers, even after limiting to English and human species. Over three hundred of them are MA papers. Emu oil is largely made up of oleic acid, an omega-9 MUFA. (6) A PubMed search for oleic acid yields over three-thousand indexed papers, ten of them being MA papers. A search for MUFA yields around 800 indexed papers, and for PUFA over four-thousand indexed papers.
Let’s see if extrapolating from this non emu oil-specific research, if required, helps in answering the claims made, for emu oil, below.
Does it Lower Cholesterol?
There has been little research in the area of emu oil and its potential cholesterol-lowering activity. One study did find it had a significant plasma total cholesterol, and low-density lipoprotein, lowering effect (-25% and -41%, respectively). However, this was in a sample of eight hamsters, over an eight-week study period, and in comparison to a sample of coconut oil-fed hamsters. Whats more, the olive oil-fed group of hamsters had an even greater reduction (-31% and -50%, respectively). (7)
Another (1999) study compared five different animal oils on cholesterol-fed rats, for a duration of 6 weeks. It found that, “the effects of emu oil...on cholesterol levels in the serum and liver were similar to those of beef tallow and lard.” (8)
The supposed cholesterol-lowering effect of emu oil has been attributed to its high content of MUFA and PUFA. (7) As oleic acid, an omega-9 MUFA, constitutes about half of the FA composition of emu oil, I ran a quick search for these terms and found minimal information. Most of the action, in this context, is with the omega-3 PUFA. There are about 30 MA papers alone. Positive results have been suggested for the cholesterol-lowering ability of omega-3. (9, 10, 11)
All well and good, but emu oils omega-3 constituent, alpha-linolenic FA, accounts for only 1.1% of the total FA’s in emu oil. Instead, why not get omega-3 directly through the diet or an omega-3 supplement? Foods high in omega-3 including fish, flaxseed (linseed) oil, walnuts and chia seeds.
Bottom Line: Minimal evidence, from animal studies of short duration, that emu oil has any cholesterol lowering properties.
Does it Reduce Inflammation & Pain? Does it Boost the Immune System & Fight Infection?
A few studies have investigated the role of emu oil in inflammation and consequent pain. However, yet again, they’ve all been conducted in experimental animals, namely mice and rats. Without clinical trials, it’s problematic to extrapolate these findings to human conditions. A 1997 study looked at adjuvant-induced arthritis in rats and found mostly positive results from topically applied emu oil (12). Another study found that orally-administered emu oil lowered acute inflammation of the small intestine, in a rat model of mucositis (13).
Omega-3 PUFA’s have been “widely described as anti-inflammatory fats”. However, the omega-3 content of emu oil is minimal at around 1%. A fairly recent review concluded that oleic-acid, the main FA present in emu oil, “could also be reported as an anti-inflammatory FA” and could play “a role in the activation of different pathways of immune competent cells”.
However, this finding was mainly based on olive oil (which is also high in oleic acid), from animal models, and the reviewers acknowledged some controversial findings in the literature. For instance, they state that “Studies in humans are lacking and the results available (from human studies) differ from the findings obtained in laboratory animals above reported”.(14)
I could not find any credible research suggesting a role for emu oil, nor oleic acid (emu oils main FA), nor omega-9 FA’s in general, in boosting immunity and fighting infection.
Bottom Line: Some evidence, from animal studies, that emu oil may have anti-inflammatory properties. No evidence for immunity-boosting properties in humans.
Does it Benefit The Gastrointestinal System?
A 2012 review investigated emu oil for inflammatory disorders affecting the gastrointestinal system. (15) It mainly reviewed the same animal studies that I mentioned above, and suggested that it could form “the basis of an adjunct to conventional treatment approaches for inflammatory disorders affecting the gastrointestinal system.”
I was unable to find any strong research (MA nor SR) for any beneficial effect of emu oil (nor oleic acid, omega-9 or MUFA) on the human gastrointestinal system. So, a biologically plausible link is difficult to make.
Bottom Line: No evidence for emu oil, or its main constituents, having any therapeutic effect on the human gastrointestinal system. Some evidence, from animal studies, suggesting a role for emu oil in inflammatory disorders of this region.
Does it Improve Skin?
Traditionally, it was the native Australian aborigines that used emu oil to accelerate wound healing and treat inflammation. (16) Apart from anecdotal information, is there any evidence for this?
There have been a few papers looking at the effect of emu oil, specifically on human skin.
A recent laboratory study, of various ratite bird oils (emu, ostrich, and rhea), on human skin cells, found that “emu oil might promote wound healing by accelerating the growth rate of keratinocytes”. (16) It goes on, further, to suggest that ratite oils may be useful additions to bandages and ointments for skin conditions.
Another laboratory study investigated the penetration enhancing effects of various natural oils. The high FA component of these oils is stated to promote skin permeability. It found that emu oil had the most penetrative ability, more so than olive oil, coconut oil and avocado oil, likely due to its high MUFA oleic acid content. (17) It has therefore been trialled as a base to better carry other compounds in to the skin, such as caffeine and Vitamin K. (21)
A pilot study, involving 42 oncology patients over a 6 week duration, tested whether emu oil could prevent radiation dermatitis during breast radiation procedures. However, they concluded that “A larger study is needed to evaluate the efficacy of emu oil” in this context. (18)
Looking at the research available for the main components of emu oil (oleic acid, omega 9, MUFA), I was unable to find any quality evidence (MA, SR) for any beneficial role in the skin or any cosmetic purposes. So, it’s not really biologically plausible for emu oil to offer such benefits.
Bottom Line: Minimal lab.-based, human skin, evidence that emu oil may directly promote wound healing. There is evidence that emu oil, as a base, may promote penetration of other ingredients across the skin and thereby, indirectly, improve the skins cosmetic appearance.
Does It Prevent Pain From Breastfeeding?
I found one paper. It studied the effect of an emu oil-based cream on breast areola skin in 70 breastfeeding Mothers. It found the cream to be significantly effective in “improving (the) stratum corneum hydration” of this region and that further tests were warranted. (19)
Looking at the research available for the main components of emu oil (oleic acid, omega 9, MUFA), I was unable to find any quality evidence (MA, SR) for any beneficial role in the prevention of breastfeeding pain. So, the biologically plausibility for emu oil to offer such benefits is questionable.
Bottom Line: Recent human trial suggesting emu oil may be beneficial for the health of the skin in the breastfeeding region, which may indirectly help to prevent breastfeeding pain. However, larger and longer-term trials are needed for results to be more conclusive.
Does It Promote Healthy Hair and Nails?
There’s not much research here, either. One study tested the effect of emu oil on superficial neck burn wounds in a sample of sixteen mice, over a two week period. It found that emu oil, despite delaying wound healing, “increases the number of hair follicles in the margins of the wound”. (20)
Looking at the research available for the main components of emu oil (oleic acid, omega 9, MUFA), I was unable to find any quality evidence (MA, SR) for any beneficial role in the promotion of healthy hair and nails. So, it’s not really biologically plausible for emu oil to offer such benefits.
Bottom Line: Minimal, animal-based, evidence that emu oil promotes healthy hair and nails.
Are There Side Effects To Emu Oil? Risks?
Emu oil appears to be quite safe, when applied topically. A recent pilot study of 42 oncology patients confirmed the “safety of oil-based skin treatments during radiation therapy and suggests a trend for reduced skin toxicity for patients receiving emu oil.” (18)
There was not too much else in the literature pointing out any harmful safety issues with emu oil, at this time.
Conclusion
As a fellow Aussie, I’d love to advocate that emu oil is a potential remedy for this and that. As you can see, though, the evidence is not there for most of the claims made, at this point in time. What is available is mostly from small-scale, mice studies. Human clinical studies are lacking. Add to this, the lack of quality control in the production of emu oil, so you’re never quite sure what you’re getting!
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