Oral Microbiota Dynamics Across the Lifespan: Age, Sex, Race and Socioeconomic Influences in the US Population

Aim

The oral microbiota, a complex and dynamic ecosystem, plays a crucial role in human health, yet systematic studies across the lifespan remain limited. This study aimed to investigate variations in the oral microbiota and the effects of key influencing factors on the oral microbiota at different age groups.

Materials and Methods

In this study, we analysed the oral microbiota of 9662 individuals aged 14–69 years from the US National Health and Nutrition Examination Survey (NHANES) to explore the impact of demographic, lifestyle and environmental factors on microbial diversity and composition. Microbiological characterisation was done using the participants' oral rinses by 16S ribosomal RNA gene sequencing.

Results

Our findings revealed a clear age-related trend in microbial diversity, with Shannon diversity peaking in middle-aged and declining in older adults. The composition of the oral microbiota also varied significantly with age, as different genera exhibited distinct abundance patterns across the lifespan. Gender and race emerged as key influencing factors, with males showing greater Shannon diversity and greater relative abundances of Atopobium, Megasphaera and Porphyromonas spp., and Whites were enriched in Rothia and Veillonella. Socioeconomic factors and lifestyle, particularly smoking, were strongly associated with shifts in microbial communities.

Conclusions

These findings provide a comprehensive overview of the dynamic changes in the oral microbiota throughout life and underscore the intricate interplay between host and environmental factors in shaping microbial composition, offering a foundation for future research on microbiota-related health interventions.