Earlier this year, I went to Morocco, where I visited Paradise Valley – a section of the Tamraght River high in the Atlas Mountains. I took a trip through parts of the Sahara desert, and to wild beaches, took a drive up to Essaouira – a city on the sea that’s beautiful and very, very windy. On each of these excursions there were stops along the way. Sometimes to look at a particularly picturesque view. Once to look at some goats grazing in the trees.
On every single trip we stopped to learn about argan oil. Argan oil – often known in the UK as Moroccan Oil – is oil derived from the fruits of the argan tree. Traditionally, argan oil was made in the Essaouira region but after Western demand increased, the production spread down to Agadir, the region where we holidayed.
Argan trees themselves grow only in the Southwest of Morocco and the argan tree is an old species – around 60 million years old. These trees are able to grow in the very arid, hot conditions of Morocco. I was genuinely surprised by how green Morocco is, and a lot of this comes from the argan tree surviving well in these conditions, supporting the growth of other plants. Their roots provide structure for the soil and the shade from their canopy allows the growth of less hardy crops (and the grazing of goats). They are important trees for the region.
The area where argan trees grow has been defined as a Biosphere Reserve by UNESCO – a region that can be used for “testing interdisciplinary approaches to understanding and managing changes and interactions between social and ecological systems, including conflict prevention and management of biodiversity”.
Argan oil production
Extracting the argan oil is a traditional practice, usually done by women, often by hand. Producing it is very labour intensive. The fruit must first be dried under the sun, before the seed is remove and then cracked open, by hand, between rocks. Inside the seed is a kernel called an almond. This can be roasted to make edible argan oil, or left unprocessed for cosmetic use.
Next the almonds are ground on a type of millstone and then water is added gradually, while kneading into a paste to release the oils. It takes 40 kilograms of dried fruit to produce one litre of argan oil. And that takes 15 hours of labour.
And this is largely women’s work – often in women’s cooperatives – so argan trees are a feminist issue as well as a climate issue.
Argan oil has been used as a traditional medicine in Morocco for hundreds of years, but more recently it has become popular worldwide as a cosmetic product. Its popularity in the UK and US began in the early 2000s. In part because Argan oil is a particularly light oil, so it’s great to use on hair and skin without feeling too greasy.
However, as with any “natural product”, it comes with a whole range of unevidenced claims. In Morocco people often use argan oil for skin complaints like dry skin and eczema – this makes some sense, in that applying an oil to dry skin can help to rehydrate it and keep some of that moisture in. It’s the same principle behind emollients for eczema. Of course, I would tend to suggest that if you have eczema, it’s best to use a very bland emollient as prescribed or recommended by a doctor, because eczema can often worsen with irritants, perfumes or allergens, which might be present in other creams or oils. But I can see how it might help in a pinch.
In terms of cosmetic use, argan oil is most commonly applied to add moisture to dry hair. I use hair oil regularly myself just to smooth down flyaways. I don’t believe it’s doing anything to change or improve my hair in the long term, but it is useful for styling for my very light, dry hair. Some people claim argan oil can cure dandruff if used as a hair mask. This isn’t based in any evidence, but using an oil on the dry skin of the scalp might help rehydrate the skin a little.
The culinary form of argan oil is claimed to be good for the immune system, as it’s high in vitamin E – vitamin E is an antioxidant that is used by the immune system, but we don’t need to supplement antioxidants in our diet in order to support the immune system. Similarly, it’s claimed the vitamin E in argan oil makes it an excellent topical treatment for wound healing due to these apparent anti-inflammatory properties. Again, there is just not enough high-quality evidence to support this claim about vitamin E itself, let alone about argan oil.
Many of the argan cooperatives I visited went further. Not only did they sell a variety of argan oils for either eating or cosmetic use, there were also many modified products to make the argan oil more useful. In some cases this was simply a case of adding fragrance or colour to the product, so that it could be used as a perfume or make up product. In other cases, the oil was added to creams to make it absorb better or be a little less oily on the skin.
There were many products that had other oils layered in, with claims they would help with a variety of other complaints, including hair loss. I hadn’t come across claims that argan oil could help with hair loss previously, but I had seen those claims made for another oil: rosemary oil.
Rosemary oil
Rosemary oil has been all over TikTok this year. Even doctors and dermatologists claim that it can be used for treating hair loss. It’s been covered in British Vogue, British GQ, Cosmopolitan. Some of that coverage has been reasonably balanced, with GQ Magazine saying:
Rosemary oil may not work for everyone, but according to a 2015 trial, participants showed a significant increase in follicle count after just six months of use. However, it’s worth noting that this was a controlled study, so it may not be an accurate representation of real-world results.
The Cosmopolitan article also mentioned the 2015 trial, saying:
[trichologist Gretchen] Oligee and dermatologist Yoram Harth, MD, also point to a commonly cited 2015 study that compared rosemary oil extract to minoxidil when used on men with genetic androgen-related hair loss.
So what about this evidence? Sadly, this 2015 study is of very low quality. It’s titled “Rosemary oil vs minoxidil 2% for the treatment of androgenetic alopecia: a randomized comparative trial”. It involved around 100 participants, which isn’t too bad, but it compares the treatment group to a different treatment – there is no placebo arm. This is a problem, because if neither treatment works, this study will be useless.
Expert dermatologists agree that 2% minoxidil isn’t really strong enough to treat hair loss. And treatments were only followed for six months; nowhere near long enough to see any true effects of a hair growth treatment. Our hair grows in cycles, and can effectively go into a dormant phase. We even have some seasonal growth, with slightly increased hair loss in the autumn and slightly increased hair growth in the spring. We need studies that are longer than six months. But that isn’t even the biggest issue with this study.
The best critique I’ve seen of this study is a video from Dr Michelle Wong, who has a PhD in chemistry and now works in cosmetic chemistry. In it she points out that two of the six crucial data points in the paper are clearly wrong. At baseline and the three-month time point they find the exact same hair count and standard deviation for each of the two test conditions (minoxidil/rosemary oil). This is practically impossible. As Michelle points out, as the measurement is literally just counting hairs, even if you did the measurements an hour apart, you would expect some minor variation in the measurements, let alone across three months. That is a pretty major error to include in a published study.
Wong also highlights that their “significant” increase in hair growth is a hair count increase of, at most, six hairs. There’s a standard deviation of 50 hairs. This is a very tiny number, in terms of hairs. The average human head has between 90,000 and 150,000 hairs. The “significant” increase here was an average of just six hairs.
Further, part of the study involves giving participants a questionnaire about their levels of depression… as one of their methods to measure hair loss. It is baffling.
So, to summarise, argan oil for hair loss: no evidence. Rosemary oil for hair loss: some evidence, but it’s pretty shabby.
As for other oils, the argan oil I saw promoted for hair loss treatment also contained cannabis oil, apparently in order to promote hair growth. Again, the evidence there is lacking. There is a study from 2021 that looked really promising, but it didn’t have a control group. It claims there was statistically significant hair growth, but claimed this based on comparing the result after six months of treatment to the original baseline of the treatment arm. That is not an appropriate way to research this issue. We know that hair loss can occur because of things like stress, childbirth or sudden weight loss, and then the hair returns naturally with time. What we are likely seeing in this paper is regression to the mean… or, at least, we have absolutely no way of ruling that out. Until a properly conducted trial is available, we should be skeptical.
What’s the harm?
Sure, argan oil might not actually be effective for the many things it’s claimed to treat, but is there any harm to using it? After all, aren’t these all natural ingredients? They’re probably therefore fine to apply directly to the scalp to see if they enhance hair growth?
Sadly, that’s not how this works – if we think a product can enhance hair growth then we must also consider that it could enhance hair loss. Acting sufficiently on the hair follicles to change their behaviour in one direction must mean causing a change in behaviour in the opposite direction is also possible. We have no evidence that these products don’t cause hair loss. Some hair loss can even be caused or exacerbated by an allergic response, so applying products that haven’t been regulated as a treatment (and therefore could have a range of other additives in there) could cause allergic reactions and harm to the scalp. Rosemary oil in particular does have some compounds that could be allergenic.
It’s also important to note that concentrated rosemary oil (ie not diluted in a carrier oil) is really likely to irritate your skin. There are some studies that show that some phytocannabinoids might lead to hair loss, too, particularly in very high doses.
As ever, the risk with cosmetic products over medical products is that the regulations are different. It can make it hard to be clear the exact doses of the active ingredients in the product. The other risk here is that hair loss can be a signifier of a serious health problem – many of which would require treatment. Looking for answers on TikTok instead of speaking to a doctor is never a good idea.
None of this means that I’m completely anti-argan oil, however. I still use some kind of hair oil in my hair almost daily (long-haired readers, don’t be aghast, I know it sounds like a lot, but my hair is so hungry for it, I still only need to wash my hair twice a week even with regular hair oil use).
Plus, argan oil production itself is probably a good thing – before it got popular outside of Morocco, deforestation was a major issue. The trees were being cut down to make way for crops and for charcoal. The tree takes around 50 years to get mature enough to grow fruit, so deforestation is definitely not good. And the ecosystem really benefits from this tree, so if trees are maintained to grow oil for cosmetic use – and produced using cooperatives with fair pay and fair-trade methods (big ifs, I know) – then it could actually be a great thing for our environment.
But, of course, there is still a risk that this industry becomes exploitative, if we aren’t careful.
