Metabarcoding analysis of gut microbiota of healthy individuals reveals impact of probiotic and maltodextrin consumption. In a previously published double-blind, placebo-controlled study, we showed that probiotics intake exerted a positive effect on sleep quality and a general improvement across time in different aspects of the profile of mood state, like sadness, anger, and fatigue in 33 of the individuals could be clustered into three groups, or bacteriotypes, at the baseline, and, inherently, bacterial compositions were linked to different responses to probiotic and placebo intakes. Interestingly, and were retrieved in the probiotic-treated cohort, while a bifidogenic effect of maltodextrin, used as placebo, was observed. The present study shed light on the importance of defining bacteriotypes