Abstract: A method of predicting a phenotypical age of a subject based on a microflora taxonomic profile of a microbiota of the subject can include: isolating a plurality of microorganism nucleic acids of microorganisms from a sample of a microbiota of the subject; analyzing the plurality of microorganism nucleic acids to determine an amount of the microorganisms of the microbiota based on the plurality of microorganism nucleic acids; generating a taxonomic profile of the microbiota of the subject based on the amount of each of the microorganisms; processing the taxonomic profile of the microbiota with a computer configured with a machine learning platform in order to predict the phenotypical age of the subject; generating a report with the predicted phenotypical age of the subject; and providing the report to the subject.