A probiotic composition is provided comprising at least two isolated bacterial species or comprising a purified bacterial preparation comprising at least two bacterial species, wherein the at least two bacterial species are selected from the group consisting of Coprococcus catus, Eubacterium rectale, Alistipes putredinis, Barnesiella intestinihominis, Roseburia hominis, Dorea longicatena and Faecalibacterium prausnitzii. Also provided are specific isolated bacterial strains and use of the composition for treating frailty and/or inflammation related to aging in elderly subjects.