Dandruff, a widespread scalp condition characterized by excessive shedding of dead skin cells, often leads to itching and irritation, affecting a significant portion of the global population. While medicated shampoos can manage symptoms, concerns regarding the toxicological profile of some common anti-dandruff ingredients, such as the EU ban on zinc pyrithione in 2022, have spurred the search for safer and effective alternatives. In this context, natural extracts with therapeutic benefits have gained attention, and Salix purpurea (purple willow) bark extract, known for its anti-inflammatory, antifungal, and exfoliating properties attributed to its salicylate content, has emerged as a promising candidate. This study aimed to evaluate the clinical efficacy and tolerability of two shampoo formulations containing different concentrations of fermented Salix purpurea bark extract as a potential treatment for dandruff and to assess its impact on overall scalp health. The fermentation process was considered as it might enhance the bioavailability of active ingredients and offer probiotic benefits for a healthy scalp microbiome.
Methods
This non-invasive split-panel study involved 21 participants with visible dandruff who used either a 2% or 4% fermented Salix purpurea bark extract shampoo for 56 days. Trichologist assessments of tolerance and clinical evaluations of efficacy, including scalp appearance, itching, redness, and dandruff visibility, were conducted at regular intervals under trichological and dermatological supervision. Macrophotography was used for visual documentation, and statistical analysis was performed to determine the significance of the treatment effects. The shampoo formulations contained a base of deionized water and included ingredients like conditioning agents (Polyquaternium-10), preservatives (Caprylyl Glyceryl Ether, Caprylhydroxamic Acid, Propanediol), surfactants (Cocamidopropyl Hydroxysultaine, Sodium Cocoamphohydroxypropylsulfonate, Sodium Cocoyl Glutamate), and other functional ingredients.
Key Findings
•Both shampoo formulations containing 2% and 4% fermented Salix purpurea bark extract were well tolerated by the participants.
•Both formulations demonstrated a reduction in dandruff symptoms throughout the 56-day study period.
•The Salixin Shampoo 4% showed a more pronounced and faster effect in reducing dandruff visibility, particularly in the initial weeks of the study.
•Trichologist assessments indicated improvement in several scalp parameters such as dry scalp, severity of dandruff, and itching with both formulations, with a slightly more dramatic improvement observed for the 4% concentration.
•By day 42, both concentrations achieved similar effectiveness in reducing dandruff, with the 4% concentration maintaining a slightly better long-term control by day 56.
•While the 4% formulation was generally more potent, it occasionally caused deterioration in sensitive skin and redness in a few cases, suggesting the 2% formulation might be gentler for sensitive skin types.
•Macrophotography provided visual evidence of the reduction in dandruff and changes in scalp redness over the course of the study for both shampoo types.
This research demonstrates the effectiveness of fermented Salix purpurea bark extract in reducing dandruff symptoms and improving scalp condition, highlighting its potential as a natural alternative to traditional anti-dandruff treatments. The novelty of this study lies in the evaluation of fermented purple willow bark extract, which may offer enhanced benefits due to improved bioavailability of active compounds and potential probiotic effects. The finding that a higher concentration (4%) provides faster relief, while both concentrations show comparable long-term efficacy, offers valuable insights for product development. Future research could explore the efficacy in larger and more diverse populations, compare it against placebo and traditional anti-dandruff shampoos, and investigate its performance in different environmental conditions to further validate its benefits and establish statistical significance. This study lays the groundwork for the development of gentle yet effective dandruff solutions based on natural fermented extracts, aligning with the growing consumer demand for safer and more natural cosmetic products.
Link to the study: https://www.tandfonline.com/doi/full/10.2147/CCID.S503915#d1e198
