Bisabolol: what are its benefits for the scalp?

The bisabolol is a natural ingredient extracted from various plants, including chamomile, candeia and beilschmiedia. It is often used in the cosmetic industry due to its multiple benefits for the skin and hair. It was from the essential oil of Chamomilla recutita, or wild chamomile, that bisabolol was first isolated in 1951.

When we delve into the chemistry of bisabolol, we find that there are two different forms existing, referred to as enantiomers : the (D)-alpha-bisabolol and the (L)-alpha-bisabolol. Only the natural and plant-based form, the L enantiomer, is active and possesses soothing, anti-irritant, anti-inflammatory, and antimicrobial properties. It is this form that is used in cosmetic care.

Bisabolol acts on scalp inflammations by soothing irritations and reducing sensations of itching. Its anti-inflammatory properties operate at various levels within cells. Bisabolol can notably reduce the activity of several pro-inflammatory cytokines, such as interleukins-1β and 6 (IL-1β and IL-6) and the tumour necrosis factor (TNF-α). Furthermore, bisabolol downregulates cyclooxygenase 2 (COX-2), an enzyme catalysing the conversion of arachidonic acid into prostaglandin H2, prostaglandins being compounds involved in inflammatory processes such as redness and itching.

A study conducted on 45 volunteers who had undergone a hair transplant recently highlighted the soothing properties of bisabolol for the scalp. Following their hair transplant, the individuals in the study had dry scalps, exhibited erythema, and experienced itching. After using a shampoo containing bisabolol for about twenty days, the researchers observed a significant reduction in the size of the scabs and erythema left by the transplant and a soothing of the itching. The concentration of bisabolol in the shampoo was not specified, but it can be assumed that it was between 0.1 and 2%, as other studies have shown that this active ingredient has proven effectiveness from 0.1%, and that a concentration higher than 2% did not provide additional benefits.

Bisabolol has a protective effect on the scalp due to its antioxidant properties. Indeed, it is capable of trapping free radicals, the reactive species generated following prolonged exposure to UV rays, pollution or tobacco, before they can damage our cells and our DNA. Furthermore, bisabolol upregulates the activity of several antioxidant enzymes such as superoxide dismutase (SOD) and catalase (CAT), which are essential for the elimination of free radicals. Indeed, SOD catalyses the dismutation of superoxide anions O2- into oxygen O2 and hydrogen peroxide H2O2. Catalase, on the other hand, ensures the dismutation of hydrogen peroxide into water and oxygen.

A hydrated scalp is less likely to be prone to tightness and irritation. Thanks to bisabolol, acting as a humectant, the water present in the scalp's epidermis is retained and insensible water loss (IWL) is minimised. In this way, bisabolol helps to maintain the skin barrier.

Note : for a more comprehensive and complete hydration, bisabolol is typically combined with other active ingredients that have a stronger hydrating power, such as thehyaluronic acid or thealoe vera.

Bisabolol contributes to the acceleration of the wound healing process. Thus, if you have a slight cut on your scalp, a bisabolol-based treatment can prove to be useful. Scientific studies have shown that this active ingredient is capable of acting at the level of the fibroblast growth factor, and increasing its activity. This allows for the intensification of collagen and elastin secretion by the fibroblasts, which is essential for the formation of scar tissue. It has also been shown that bisabolol can promote the multiplication and migration of fibroblasts towards the wound area.

For 1 in 2 people, dandruff is a common scalp disorder. Several factors have been identified as contributing to the onset of dandruff, among which is an overgrowth of Malassezia type fungi. By hydrolysing the triglycerides present in sebum, these pathogens are responsible for the production of pro-inflammatory mediators. In addition to helping combat inflammation, bisabolol acts at the source and inhibits the synthesis of compounds essential to the integrity of the fungal cell membrane . This dual action explains why it is frequently found in anti-dandruff shampoos.

• RIPPKE F. & al. Highly efficient and compatible shampoo for use after hair transplant. Clinical, cosmetic and investigational dermatology (2015).

• ELGINDI N. & al. α-Bisabolol-Loaded Cross-Linked Zein Nanofibrous 3D-Scaffolds For Accelerating Wound Healing And Tissue Regeneration In Rats. International journal of nanomedicine (2019).

• OJHA S. & al. Health Benefits, Pharmacological Effects, Molecular Mechanisms, and Therapeutic Potential of α-Bisabolol. Nutrients (2022).