The human gut microbiome across the life course

Area of Science:

• Microbiology
• Human Physiology
• Gerontology

Background:

• The gut microbiome shows significant variation across individuals throughout the human lifespan.
• Age-specific compositional and functional patterns emerge due to factors like early seeding, environmental exposures, and aging.
• Early life events, including birth and feeding, establish the initial microbiome, often favoring Bifidobacterium.

Purpose of the Study:

• To review current evidence on the human gut microbiome across the lifespan.
• To identify priorities for developing microbiome-informed interventions tailored to different life stages.
• To explore the potential of microbiome aging clocks for indexing biological age.

Main Methods:

• This review synthesizes existing scientific literature on the gut microbiome.
• Analysis of compositional and functional changes across infancy, childhood, adolescence, adulthood, and older age.
• Evaluation of factors influencing microbiome stability and unique profiles in later life.

Main Results:

• The gut microbiome undergoes significant restructuring from infancy through adolescence.
• Adult microbiomes exhibit functional redundancy for stability, while older adults show greater uniqueness.
• Healthy older adults and centenarians may retain metabolic capacities that buffer inflammaging.

Conclusions:

• Microbiome composition and function evolve across the human lifespan.
• Further research is needed to overcome limitations in developing microbiome aging clocks.
• Life-stage-tailored interventions are a priority for optimizing gut health.