5 natural Australian hair and scalp care ingredients

Consumers are increasingly seeking natural ingredients in hair and scalp care products. Here are the top Australian natural ingredients that will meet consumer demand.

Natural hair and scalp care products are set to boom, as consumers seek hair care products without harmful ingredients such as sulfates and parabens.

In 2024, online searches for "sustainable hair care" rose by 716%, while "all natural" searches rose by 148%.¹

Consumers also sought particular natural ingredients, with searches for Tea Tree Oil rising by 176% and Aloe increasing by 136%.¹

Dee-Ann Prather, Founder and CEO of Down Under Enterprises Australia, a grower, producer and wholesaler of pure Australian Essential Oils and native Australian botanicals, says: "Consumers are demonstrating an awareness and care for our planet and their bodies. This gives manufacturers and retailers of natural hair and scalp products an opportunity to meet that demand and grow their business."

Scalp health is a systematic

There is a growing recognition that healthy hair requires a healthy scalp. However, scalp health involves multiple mechanisms which natural products need to address:

• supporting the skin microbiome, which involves balancing levels of commensal ("good") microbes while controlling levels of transient ("bad") microbes; and

• supporting healthy biochemical processes, which affect the action of the sebaceous glands and oil production; and

• supporting skin as our largest immune system, which affects inflammatory responses and hence blood flow to the follicles.

There are 5 key natural Australian botanicals in hair and scalp care that have growing evidence of efficacy in supporting these mechanisms.

Australian Tea Tree Oil 

Melaleuca alternifolia

The use of Tea Tree Oil in hair care has increased 7 times in the last 5 years – and for good reason.²  This powerhouse ingredient has anti-inflammatory, anti-itch, antifungal, and antibacterial properties. It's comparable to common synthetic fungicides against Malassezia yeasts, yet it has an extremely low risk of skin irritation.

Tea Tree Oil supports the scalp's microbiome to help control dandruff

For consumers, Tea Tree Oil offers demonstrated improvements in dry, itchy, and flaky skin conditions.

It's effective against dandruff-causing Malassezia yeasts, even at low concentrations. One study showed that Tea Tree's minimum inhibitory concentration (MIC, i.e. the lowest concentration of a substance that prevents visible in vitro growth of bacteria or fungi) was significantly lower than two common synthetic fungicides, miconazole and econazole.³

A randomized controlled trial (n=126) found that the use of 5% Tea Tree Oil over 4 weeks resulted in a 41% improvement in dandruff severity compared with 11% in the placebo group (p<0.001), as well as improvements in greasiness and itchiness.⁴

Penetrative action boosts biochemical scalp function

The scalp has a high concentration of sebaceous glands which makes it prone to seborrheic dermatitis.⁵

While typical personal care cleaning products such as alcohol amines and tetracycline only remove the surface layer of skin lipids and cannot reach clogged sebaceous glands, Tea Tree Oil has been shown to directly reach sebaceous glands, supporting the dispersion and removal of excess sebum.^6–8

Tea Tree Oil and the immune system

Tea Tree Oil is well-known for its antimicrobial efficacy across a wide range of organisms. ^9–11

It's less well-known that the high concentration of terpinen-4-ol in Tea Tree Oil is a well-documented anti-inflammatory which can support blood flow and scalp health.^12,13

Tea Tree Oil for hair loss

In a clinical study of 32 men for 32 weeks, a 5% concentration of Tea Tree Oil combined with the hair loss treatment minoxidil was significantly superior to minoxidil alone or placebo in terms of hair count, weight, growth and thickness.¹⁴

Formulation tip

Tea Tree Oil is being suggested as an addition to, or replacement for, traditional anti-dandruff ingredients such as zinc pyrithione.

AUSTRALIAN LEMON-SCENTED TEA TREE OIL

Leptospermum petersonii

Australian Lemon Scented Tea Tree Essential Oil is a different species from Tea Tree Oil. It's rich in citral, a chemical compound that provides a fresh and uplifting aroma. This essential oil has antibacterial, anti-fungal, anti-inflammatory and antiseptic properties and is a natural head lice deterrent. Its fresh scent makes it ideal to mask the odor of Tea Tree Oil while conveying synergistic benefits.

Action on the microbiome: head lice treatment

This oil is effective against head lice, particularly when paired with Eucalyptus Oil. A randomized controlled trial showed that a blend of Lemon Scented Tea Tree Oil (0.5%) and Eucalyptus Oil (9%) was significantly more effective (p<0.0001) than a pyrethrin/piperonyl butoxide commercial preparation for curing head lice infestation, with no sensitization or irritation.¹⁵

Immune system activity

Lemon Scented Tea Tree Oil is effective against a variety of microorganisms, and it boosts the antimicrobial activity of Tea Tree Oil. One study showed that a combination of Lemon Scented and Tea Tree Oil in a 1:5 ratio, respectively, was four times more potent against S. aureus than Tea Tree Oil alone.¹⁶

It is theorized that the high citral content of Lemon Scented Tea Tree Oil helps the Tea Tree Oil to penetrate the bacteria's phospholipid cell wall.

Lemon Scented Tea Tree Oil is a potent antioxidant,¹⁷ which is important for scalp care, since oxidation releases free radicals that stimulate inflammatory processes affecting the skin.

Formulation tip

Lemon Scented Tea Tree Oil is a powerful partner to boost the efficacy of products containing Eucalyptus Oil or Tea Tree Oil.

At a 1:7 ratio, Lemon Scented Tea Tree Oil can be used to mask the herbaceous odor of classic Tea Tree with a more appealing fresh lemon scent.

AUSTRALIAN EUCALYPTUS OIL

Eucalyptus kochii

Australian Eucalyptus Oil offers therapeutic benefits for an inflamed and dry scalp, including antiseptic and anti-inflammatory properties.

Antibacterial action supports the microbiome

Eucalyptus Oil is effective against the organisms implicated in scalp folliculitis, Staph aureus and Cutibacterium acnes.¹⁸

Biochemical effects

Eucalyptus Oil improves the condition of the scalp because it contains macrocarpal A, a compound that appears to stimulate ceramide production. A 4-week study of people with seborrheic dermatitis or dandruff showed that Eucalyptus decreased scalp redness, itchiness, dryness, and scaliness, with symptoms improving from week 2.¹⁹

Immune system activity

Eucalyptus Oil may support the scalp's immune system by increasing circulation, a critical element for healthy hair and hair loss prevention.²⁰

Formulation tip

Australian Eucalyptus Kochii Oil has a natural 1,8-cineole level of over 90% with one distillation, making it an effective ingredient for natural scalp care and anti-dandruff products – and it retains more natural aromatic characteristics beyond cineole.

MANUKA OIL

Leptospermum Scoparium

Manuka Oil kills gram-positive bacteria and fungi, even at low concentrations. Its actions make it the perfect partner to Tea Tree Oil.

Microbiome support

Manuka Oil is highly effective in haircare formulations as it can kill bacteria and fungi that cause or worsen dandruff. The secret to its efficacy is its high level of β-Triketone which means that only a small percentage of oil is needed for maximum antimicrobial efficacy – only a 0.091% concentration is needed for a 99% kill rate against S. aureus, for example.²¹

Manuka Oil vs dandruff-related microbials

MIC: the lowest concentration of a substance that prevents visible in vitro growth of bacteria or fungi.

Immune support

Studies have shown that 0.1–10% Manuka Oil significantly reduced the release of TNF-α, an inflammatory mediator, so it could combat scalp irritation.²²

Formulation tip

Manuka Oil and Tea Tree Oil are a dynamic duo. They're powerful antimicrobials when used individually but when used together their potency increases.

Adding a very small amount of Manuka to Tea Tree Oil will increase its activity against S. aureus by 73%, for example.²³

Manuka Oil has had substantial growth in Europe and Asia in the last two years, so there is a huge potential for growth in North America.²

AUSTRALIAN SANDALWOOD SEED OIL

Sandalwood spicatum

Sandalwood Seed Oil is naturally high in ximenynic acid, a natural anti-inflammatory, which helps to increase blood circulation and promote scalp health and hair growth.

Biochemical activity supports healthy oil balance

The ximenynic acid in Sandalwood Seed Oil blocks the arachidonic LOX (and COX) inflammation pathways, which helps increase blood circulation to the skin.

It has the potential to reduce hair loss through enhanced blood flow to hair follicles, in a similar action to the hair-loss treatment minoxidil.  

Immune effects

The structure of ximenynic acid is similar to enzymes that catalyze arachidonic acid and block inflammation pathways, making it useful to combat an itchy and inflamed scalp. An in-vitro study showed it to be clinically active at a 7% dilution ratio.²⁴

Formulation tip

Sandalwood Seed Oil can be used just like any other fatty carrier oil like jojoba or argan oil. It contains no cosmetic allergens and is suitable for sensitive skin.

ADDITIONAL FORMULATION TIP

Hydrosols: Not essential oils, but essential to product success

Hydrosols are low-cost, natural and sustainable, all attributes that consumers are seeking.

They can be used as a water replacement at up to 100% in formulas and are naturally lathering and softening, which may reduce the amount of surfactant needed and potentially reduce costs.

Australian hydrosols are available in a range of aroma profiles, including Tea Tree, Lemon Myrtle, Fragonia, Sandalwood and Lavender.

Not all natural ingredients are reliable

When working with natural botanicals, it's crucial to understand that they can vary in quality and potency based on growing conditions, harvest timing, and processing methods. Brand owners and manufacturers need to collaborate with credentialed experts specializing in the practice.

"When using botanicals, it is so important to have a trustworthy source," emphasizes Dee-Ann Prather. "Product manufacturers should ensure they are womustrking with experts taking care of the plants with the proper credentials and in a sustainable way to get the long-term benefits of nature."

References:

1. NielsenIQ Label Insight Trending Attributes, 3 months ending Jan 2024.
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