Effect of two shampoo formulations on the prokaryotic and eukaryotic microbiota composition of the human scalp.

Over an application period of two weeks, the investigated shampoo induced quantitative, but no qualitative changes in the scalp microbial community structure of the investigated probands, suggesting no adverse but rather preserving or even stimulating effects of the underlying formulations on the scalp microbiota. Further investigation will have to clarify if this is also true for longer application periods and if the formulations might affect community functionality, e.g. microbial gene expression, rather than community composition.