Supplementary Material for: A selenium disulfide-based shampoo is beneficial for dandruff management and rebalancing the scalp microbiome of subjects of any hair type

Introduction
Dandruff is a scalp condition occurring in all hair types (de la Mettrie scale I to VIII). Selenium disulfide (SeS2) is beneficial in dandruff and rebalances the scalp microbiome. Data regarding subjects with curly hair are missing.
This study assessed the clinical and scalp microbiome benefits of SeS2 shampoo in subjects of any hair type with moderate-to-severe dandruff.
Methods
A 6-week study in adults of any hair type assessed total dandruff, SD severity score (SSSD), erythema, hair greasiness, quality of life (QoL), discomfort, local tolerance, subject perception and changes in the scalp microbiota. SeS2 shampoo was applied twice every week.
Results
93 subjects (women: 83%) were recruited. 69% were of European and 31% of African origin. SSSD and total dandruff scores were the highest in hair type IV-V, erythema scores in hair type I-III, and the itching score in hair type VI-VIII, . After 4 weeks, signs and subject assessments had significantly (all p<0.05) decreased. SeS2 shampoo significantly (p<0.001) rebalanced the scalp microbiome. All subjects highly appreciated SeS2 which shampoo was well tolerated.
Conclusion
SeS2 shampoo is beneficial in moderate to severe dandruff, and rebalances the scalp microbiota in all hair types. SeS2 shampoo was highly appreciated by the subjects.