The Effects of Caffeine and Adenosine on the Microbiome and Lipidome of the Scalp

May 2025 in “ International Journal of Cosmetic Science ”

Fengzhu Li, Shu‐Lin Liu, Zhaoying Han, Yingtian Li, Haowei Chen, Qingying Shi, Jie Tan, Xihong He, Xinyan Liu, Huabing Zhao, Fang Wang

caffeine adenosine scalp microbiome lipidome hair density hair shedding hair intensity Pseudomonas Escherichia-Shigella Cutibacterium Malassezia Talaromyces

From the encyclopedia

Caffeine →

the stimulant you know and love can be used topically to stimulate hair

Adenosine →

nucleoside used for hair regrowth stimulant properties

Studysummary In this study, researchers found that a shampoo containing caffeine and adenosine significantly altered the scalp microbiome and lipidome in subjects with hair loss over 12 weeks, which may suggest a role for these compounds in enhancing anti-hair loss processes.

Our plain-language summary. Not medical advice or a treatment recommendation. Consult a qualified healthcare professional before changing treatment. Full disclaimer

This study examined the effects of a shampoo containing caffeine and adenosine on the scalp microbiome and lipidome in 30 individuals with hair loss over 14 weeks. The experimental group using the active shampoo showed a 55% increase in hair density in 8 weeks, reduced hair shedding, and increased hair intensity, although hair diameter remained unchanged. Significant changes were observed in the scalp's bacterial and fungal communities, including decreases in Pseudomonas and Escherichia-Shigella and an increase in Cutibacterium, as well as a decrease in Malassezia and an increase in Talaromyces. Lipid analysis revealed 39 significantly altered lipids, with some correlating with hair characteristics. These findings suggest that caffeine and adenosine may promote hair growth by modulating microbial and lipid profiles, though the study notes limitations such as a small sample size and gender imbalance, indicating the need for further research.

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