Towards Best Practice in Hair Metabolomic Studies: Systematic Investigation on the Impact of Hair Length and Color

The study investigated the influence of hair color and length on the analysis of endogenous metabolites in hair samples, which is important for retrospective monitoring of metabolome changes. Using untargeted data acquisition, the research analyzed metabolites in genuine hair samples from individuals with different hair colors and segmented the hair into 3 cm lengths. The findings revealed significant differences in metabolite profiles based on hair color and along the length of the hair strand. Consequently, the study concluded that both hair color and segment length must be considered in hair metabolomic studies and provided recommendations for best practices in this field of research.