Chinese researchers recently assessed the causal relationships between the human microbiome and longevity, finding certain types of microbes were related to increased or decreased odds of longevity.Although previous studies managed to reveal the association between the human microbiome, especially gut microbiota, and longevity, their causality remained unclear.The researchers from the University of Chinese Academy of Sciences, Zhejiang University, Peking University, Fudan University and BGI-Shenzhen used Mendelian randomization analyses, based on genome-wide association studies, to find the causal relationships between human gut and oral microbes, and human longevity.The study, which was published in the journal Scientific Reports, found that some disease-protected gut microbe groups were related to increased odds of longevity. The study also revealed that other gut microbes, such as the colorectal cancer pathogen, were negatively associated with longevity.The study further showed that genetically longevous individuals tended to have higher abundances of certain microbe groups, such as Prevotella and Paraprevotella, but lower abundances of Bacteroides and Fusobacterium species.Centenarians genetically had a lower gut microbial diversity, but no difference in oral microbes compared with other age groups, according to the study.The researchers also suggested that it is necessary to monitor the relocation of commensal microbes among different body sites of humans to improve their chances of living long and healthy lives.Chinese researchers recently assessed the causal relationships between the human microbiome and longevity, finding certain types of microbes were related to increased or decreased odds of longevity.Although previous studies managed to reveal the association between the human microbiome, especially gut microbiota, and longevity, their causality remained unclear.The researchers from the University of Chinese Academy of Sciences, Zhejiang University, Peking University, Fudan University and BGI-Shenzhen used Mendelian randomization analyses, based on genome-wide association studies, to find the causal relationships between human gut and oral microbes, and human longevity.The study, which was published in the journal Scientific Reports, found that some disease-protected gut microbe groups were related to increased odds of longevity. The study also revealed that other gut microbes, such as the colorectal cancer pathogen, were negatively associated with longevity.The study further showed that genetically longevous individuals tended to have higher abundances of certain microbe groups, such as Prevotella and Paraprevotella, but lower abundances of Bacteroides and Fusobacterium species.Centenarians genetically had a lower gut microbial diversity, but no difference in oral microbes compared with other age groups, according to the study.The researchers also suggested that it is necessary to monitor the relocation of commensal microbes among different body sites of humans to improve their chances of living long and healthy lives.