Does eucalyptus oil for hair work? Claims vs Evidence 

We’ve tried lavender oil, cedarwood oil, and black seed oil…but the quest for long and luscious hair continues. In this post, we’ll look at the benefits of eucalyptus oil for hair.

You may have been told that this oil will solve all your hair care needs, but will it work? Let’s look at the claims and evidence.

Contents

• Types of eucalyptus oil
• Eucalyptus oil for hair: claims vs evidence
• Eucalyptus oil as a cure for head lice
• Eucalyptus oil for hair growth
• Eucalyptus oil as an anti-dandruff treatment
• Eucalyptus oil to prevent sun-damaged hair
• Eucalyptus oil for hair shine
• Conclusion: our expert advice

Types of Eucalyptus essential oil

Before we get into the nitty-gritty, there’s one important thing to note: not all eucalyptus oils are equal.

Here's a few different types of eucalyptus tree that are used to create essential oil: 

• Camaldulensis
• Globulus
• Maidenii
• Plenissima
• Polybractea
• Radiata
• Smithii

They are all made up of different mixtures of natural aroma chemicals, and you'll notice that they smell different too.

When we look at the evidence, pay attention to what type is being used, compared to the type you’re considering buying. 

You can’t expect the same results with different oils!

(P.s. our eucalyptus essential oil is eucalyptus globulus)

Eucalyptus for hair: claims vs evidence

Advocates of eucalyptus oil for hair will praise its ability to:

• Cure headlice
• Stimulate hair growth
• Treat dandruff
• Prevent sun-damage
• Improve hair shine
• Cure itchy scalp
• Improve blood circulation to the hair follicles
• Generally improve hair health

While we love the oil for its refreshing scent and therapeutic properties, we know there’s a lot more research to be done on its haircare benefits.

Let’s take a closer look at the studies behind the claims...

Eucalyptus oil as a cure for head lice

Here's the first claim: Eucalyptus essential oil can be used to treat head lice.

Remember having your hair vigorously combed after a school hair lice outbreak? We’re willing to do anything to get rid of these little pests, and some say eucalyptus oil can do just the trick.

But what's the evidence that this works? Here's the two studies used to prop up this claim.

Study 1: A natural alternative to conventional treatments

In one study, Australian essential oils were compared to common treatments on school children with head lice.

Researchers concluded that the essential oils were an effective natural alternative to conventional treatments, but it’s not clear whether the results were down to eucalyptus oil, or the lemon-scented tea tree oil also in the solution. 

How many people took part in the study?
76 primary school children with live head lice (not just eggs) on the hair or scalp. This was determined by dry combing the hair with a head lice comb.

Which oil did they use?
11% Australian eucalyptus oil. We don’t know if it is eucalyptus globulus, or any other type.

Did they give a treatment recipe?
They used a headlice solution by Australian brand MOOV, which contains 11% eucalyptus oil and 1% leptospermum petersoni (lemon-scented tea tree oil).

How much treatment was applied?
We don’t know the quantity, but it was applied three times over 21 days (so once a week).

Study 2: Spray formulation against resistant headlice

Another study investigated spray formulations for treating headlice that were resistant to conventional treatments.

The results showed that a eucalyptus treatment was more effective in killing the headlice than a clove oil treatment and a treatment that contained a mixture of both oils. 

How many people took part in the study?
No people, just human hair wigs.

Which oil did they use?
Clove and Eucalyptus essential oils (the globulus variety)

Did they give a treatment recipe?
Yes, one of the spray treatments contained: 

• 8% eucalyptus oil
• 5% emulsifier
• 20% ethyl alcohol
• 67% water

It’s a tricky one to replicate at home but it could be possible.

How much treatment was applied?
10-20ml of solution was applied to each wig

Summary: Can Eucalyptus oil cure hair lice?

We can claim that eucalyptus oil may help treat headlice as there’s evidence that eucalyptus oil does kill drug-resistant headlice in the lab. 

Interestingly the second study found that eucalyptus essential oil is more effective than a eucalyptus and clove mixture.

That said, more human studies are needed to be sure.

Eucalyptus oil for hair growth

Here's the next big claim: Eucalyptus essential oil can make your hair grow.

You'll find it repeated in blogs everywhere, but does the claim hold water?

The idea that eucalyptus oil can speed up hair growth isn’t built on direct evidence, but a tenuous link between studies:

Inflammation can cause hair loss → Eucalyptus oil has anti-inflammatory properties → Eucalyptus oil might reduce scalp inflammation and create a better environment for hair growth.

That should already make you sceptical.

Lets find out what studies are used to support this claim...

 

Study 1: Eucalyptus oil as an anti-inflammatory

This study found that eucalyptus globulus isn’t an effective anti-inflammatory treatment in mice, whereas eucalyptus citridora is.

It doesn’t tell us anything directly about human hair growth 

How many people took part in the study?
None. The study used rats and mice.

Which oil did they use?
Eucalyptus citriodora, eucalyptus tereticornis, and eucalyptus globulus. 

Did they give a treatment recipe?
No, it’s not mentioned.

How much treatment was applied?
They injected 0.1, 10, and 100 mg/kg of each essential oil. 

Definitely don't try this at home!

Study 2: Scalp Inflammation and hair growth

Another study that’s commonly referred to for this claim, concludes that carvacrol, a component of thyme oil, could be an effective anti-inflammatory agent. 

We don’t know about you, but we’re struggling to see how it applies to eucalyptus oil for hair growth.

How many people took part in the study?
None. Instead, various cells were grown in a lab.

Which oil did they use?

Thyme, clove, rose, fennel, bergamot and eucalyptus essential oils

Did they give a treatment recipe?
No recipe was given. 

How much treatment was applied?
There’s no information on this either.

This study wins the prize for being the first study to get only one tick on our list of criteria. It fails in every other area.

The only good thing about this study is that they did actually use eucalyptus oil!

Summary: Can eucalyptus oil help hair growth?

Since it requires a whole story to reach this claim, we think it’s extremely unlikely to be true.

Firstly, inflammation is only one of many factors causing hair loss. Not to mention, preventing hair loss isn’t the same as encouraging hair growth.

Secondly, none of the studies were done on the scalp, so there’s no evidence that eucalyptus oil can reduce scalp inflammation anyway.

Lastly, the whole logical link between anti-inflammatories promoting hair growth is flimsy.

We'd say these claims are definitely hope over reason!

Eucalyptus oil as an anti-dandruff treatment

The next claim you'll probably encounter on other blogs is that eucalyptus oil is a great anti-dandruff treatment.

Most of us will experience dandruff at some point in our lives. It’s itchy, irritating, and affects half the adult population.

Some say eucalyptus oil, with its antibacterial and antifungal properties, can make for an efficient anti-dandruff treatment.  

So what studies are people leaning on to support this claim?

Study 1: Dandruff caused by Malassezia Furfur fungus

This study shows that eucalyptus could be useful if your dandruff is caused by the fungus Malassezia furfur.

However, it hasn’t been tested in humans and the dilutions tested in this study are unsafe for the skin.

How many people took part in a study?
No people. This study examined the essential oils, diluted with coconut oil, against the dandruff-causing fungus Malassezia furfur in a lab setting.

Which oil did they use?
Eucalyptus globulus

Did they give a treatment recipe?
The essential oil was diluted to 25%, 50%, and 75% with coconut oil. 

The safe limit for eucalyptus oil for skin is 20% and since all 3 dilutions are above this, it’s dangerous for humans to try.

How much treatment was applied?
Not specified. 

Study 2: Dandruff caused by Rice Blast Fungi

This study looks at eucalyptus oil against another fungus: rice blast fungus.

It found that eucalyptus oil exhibited strong antifungal activity, but since the fungus lives in rice fields, we think it’s unlikely to be the cause of your dandruff.

How many people took part in the study?
No people were involved in the study. The method used a laboratory experiment instead.

Which oil did they use?
Eucalyptus. grandis × E. urophylla (not a common type of eucalyptus oil in the UK).

Did they give a treatment recipe?
They used 0.5 mg/ml of eucalyptus oil.  

How much treatment was applied?
The oil was applied to the rice blast fungi and were checked after 5 days and 7 days of culture. 

Summary: Can eucalyptus oil treat dandruff?

Overall, we think eucalyptus oil is unlikely to help dandruff.

While eucalyptus globulus can be used as a natural antidandruff agent, there is no evidence that it works for real people at any safe dilution.

Eucalyptus oil to prevent sun-damaged hair

Here's another claim mentioned across the internet: Eucalyptus essential oil can help prevent the sun damaging your hair.

UV rays from the sun not only damage our skin but can dry out our hair too. Can eucalyptus help?

Lets take a look at the evidence to find out more...

Study 1: Eucalyptus and UV protection

This report investigates the protective effects of eucalyptus extract against UV-induced skin aging.

It concludes that the plant extract be used as an effective ingredient in skin care products to protect against sun damage, and so has been used to back up this claim. 

There’re two key things here: the study used eucalyptus extract, not essential oil, and looked at the effect on the skin, not hair. When it comes to eucalyptus oil for hair it’s – you guessed it - irrelevant.

How many people took part in the study?
None, as it was conducted using cell culture experiments.

Which oil did they use?
The study used Eucalyptus globulus extract, not essential oil.

Did they give a treatment recipe?
No specific treatment recipe was given.

How much treatment was applied?
Again, no specific details were given.

This study managed to meet only one of our criteria for a useful study. Fail!

Study 2: Heat-protective scalp lotion

In a long-term investigation of a scalp lotion containing eucalyptus extract, it was found to prevent hair damage caused by UV radiation and heat treatment. 

The authors concluded that eucalyptus extract could be a beneficial ingredient for heat protection hair products. Although, unlike the previous one, this study looks at hair, it also uses eucalyptus extract not essential oil.

How many people took part in the study?
It doesn’t say.

Which oil did they use?
A scalp lotion containing eucalyptus extract.

Did they give a treatment recipe?
No, they only say ‘half-head or whole-head usage’, whatever that means!

How much treatment was applied?
It doesn’t specify an amount,  just ‘long-term usage’.

This isn't even really a study, and it adds nothing to the evidence at all.

Summary: Does eucalyptus oil protect your hair from the sun?

Considering that both of the studies didn't even use eucalyptus oil, we're shocked anyone is using them to back up their claims.

It's complete nonsense.

Eucalyptus oil for hair shine

The last claim on our list is that eucalyptus oil can give you the shiny glossy locks you desire. That’s the dream, but is it reality?

Many vague anecdotes are used in relation to this claim, as well as this paper that is often used as evidence.

Study 1: Hair nourishing shampoo (allegedly)

This study uses eucalyptus oil alongside onion extract in a shampoo, which it says promotes hair growth. 

It’s more a personal shampoo recipe than a scientific study. We don’t particularly trust it either, because 2 out of the 3 recipes have a pH high enough to dissolve your hair (the exact opposite of what we’re looking for).

How many people took part in a study?
Not mentioned 

Which oil did they use?
Eucalyptus oil, it doesn’t specify the type.

Did they give a treatment recipe?
Yes, the shampoo was made of: 

• coconut oil
• castor oil
• potassium hydroxide
• glycerol
• borax
• acacia
• allium cepa extract
• eucalyptus oil
• sodium bicarbonate
• lemon juice
• methylparaben
• perfume
• distilled water 

Phew!

How much treatment was applied?
It doesn’t mention how much, it just mentions three different formulations: F1 (pH 14), F2 (pH 13), and F3 (pH 10).

Conclusion: Does eucalyptus oil make hair shiny? 

There may be some anecdotal evidence that eucalyptus oil can improve hair shine, but there’s no solid research behind this claim. 

Eucalyptus oil for hair: our expert advice

It’s safe to say eucalyptus oil is unlikely to transform your hair overnight. There are a lot of claims, but no solid evidence, for its haircare benefits.

Don’t let that put you off, though. Its refreshing scent works perfectly in shampoo bars, soaps, and other cosmetics. As long as you stick to the maximum limit of a 20% dilution, it won’t do your hair any harm and, who knows, maybe you’ll discover your own benefits.

Continue reading

Now you've learned about eucalyptus oil benefits for hair, why not continue reading?

• Interested in essential oils for hair growth? Read more about rosemary essential oil for hair
• Want to learn more about tea tree essential oil? See if tea tree oil can help with acne
• Have you heard claims that essential oils can help treat burns? Read more about lavender oil for burns

Do you use any essential oils in your haircare routine? Let us know in the comments!