Sarcopenia-related gut microbiota in the elderly: Insights from the longevity region of Kyotango and its nutritional associations

Sarcopenia is influenced by the gut microbiota and dietary habits; however, the underlying mechanisms remain elusive. This study investigated the gut microbiota composition of elderly individuals in a healthy longevity region and examined its association with sarcopenia and dietary habits. Fecal metagenomic analysis was used to identify gut microbiota taxonomy. Sarcopenia was diagnosed on the basis of grip strength, gait speed, and muscle volume. Japanese dietary habits were assessed using a brief-type self-administered diet history questionnaire. A total of 318 elderly individuals from Kyotango were recruited, 5.7% of whom were diagnosed with sarcopenia. Individuals with sarcopenia exhibited a lower abundance of a genus belonging to the family Lachnospiraceae, and a higher abundance of Megasphera. Several butyrate-producing bacteria, including Lachnospira and Coprococcus showed a positive correlation with sarcopenia related factors, whereas Dorea and Streptococcus were negatively correlated. Hierarchical cluster analysis revealed that these beneficial genera were also positively associated with the frequent intake of traditional Japanese dietary components. These findings suggest that the observed microbial and dietary associations may provide a mechanistic basis for potential protective effects against sarcopenia. Our findings suggest that butyrate-producing bacteria associated with Japanese dietary patterns play a protective role against sarcopenia.