<p>The diversity of microbial communities on the fingers and in the oral cavity may vary based on the regularity of shared daily routines. Participants who frequented various shared spaces, including daycare centers, offices, senior centers, universities, and mosques, provided oral and finger-swab samples. Samples from individuals who regularly shared spaces showed a high similarity in the diversity of finger microbial communities, highlighting the significant role of environmental exposure. Participants associated with shared spaces had low intra-group variation, indicating consistent microbial exchange. In contrast, oral microbiomes were less affected by regular shared spaces and were more influenced by factors such as diet, hygiene, and demographic characteristics. Participants in the irregularly shared space group showed higher levels of similarity in oral microbiomes, with notable differences in microbial diversity among groups based on their unique cultural, dietary, and hygienic practices. Overall, this study demonstrated that regular interactions within specific environments can significantly shape microbial profiles, particularly on the skin, whereas oral microbiomes are more stable and influenced by broader lifestyle factors.</p>