Name: how early feeding shapes the gut microbiota
Uploaded: 2026-03-12T13:35:51.000Z
Duration: 1 min 30 s
Channel: JoVE

The development of human microbiota begins at the time of birth.Newborns get microbes from the mother. Vaginal delivery is associated with colonization by Bifidobacterium and Bacteroides, while cesarean delivery is linked to colonization by Staphylococcus and Corynebacterium.In infants, breast milk promotes the growth of Bifidobacterium species by providing oligosaccharides that specifically serve as nutrients for these bacteria.As the infant's diet transitions to include solid foods, microbial diversity increases, and adult-associated taxa such as Bacteroidota and Bacillota become more prominent.By the age of three, the gut microbiota stabilizes into a more adult-like composition.In adulthood, the gut microbiota remains relatively stable but varies greatly between individuals and is influenced by diet, lifestyle, and major life events.With aging, microbial diversity often decreases, with a notable shift in the balance of Bacillota and Bacteroidota, and reduced levels of beneficial Bifidobacteria.Maintaining a diverse, balanced gut microbiota supports metabolic health, immune function, and may influence longevity.

development of human microbiota

Development of Human Microbiota

The human microbiota begins developing at birth and undergoes continual change as we age. Infancy marks a critical period of microbial sensitivity, offering a &#8220;window of opportunity&#8221; during which beneficial microbes help mature the immune system. By age three, children typically develop a more stable and diverse microbial community. Newborns acquire microbes from their immediate environment; vaginal delivery favors maternal vaginal microbes, while cesarean births favor microbes from the skin and surroundings. Current studies are investigating the potential benefits of exposing C-section newborns to maternal vaginal microbes to compensate for this difference.Breast milk plays a selective role in nurturing beneficial bacteria such as Bifidobacterium by providing oligosaccharides that these microbes can metabolize. Their fermentation byproducts&#8212;acetate and lactate&#8212;not only nourish the infant but also acidify the gut, impeding pathogenic growth. Transitioning to formula or solid foods leads to a decline in Bifidobacteria and a rise in other gut microbes like Bacteroidota and Clostridia. During the first year, the infant gut transitions from a relatively simple to a more complex microbiome, enriched in genes for vitamin synthesis and energy production.Delivery method and early diet significantly affect microbial colonization. Vaginally delivered infants share a larger proportion of microbes with their mothers, including beneficial genera like Bifidobacterium and Lactobacillus. Infants born by C-section show greater colonization by skin and environmental microbes. Breastfeeding further promotes beneficial species and microbial diversity, on the other hand to formula feeding, which is associated with potentially pathogenic species like Clostridium difficile. By 12 months, the microbial differences between delivery types narrows, though C-section infants still show more heterogeneous communities. Cessation of breastfeeding&#8212;not the introduction of solids&#8212;is what most significantly triggers the formation of an adult-like microbiota.In adulthood, the gut microbiome remains relatively stable over time, with species belonging to Bacteroidota and Actinobacteria persisting the longest. Aging alters this balance, often decreasing Bacillota (previously Firmicutes) and microbial diversity&#8212;especially among those in institutional care. Reduced diversity in the elderly is linked to increased frailty, suggesting that maintaining a varied microbiota may promote longevity and overall health.

The human microbiota begins developing at birth and undergoes continual change as we age. Infancy marks a critical period of microbial sensitivity, ...

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JoVE Core

Microbiology

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Human Microbiome and Virome

KEY TERMS AND CONCEPTS

how early feeding shapes the gut microbiota

The human microbiota starts forming at birth and changes as a person grows. The first years are a sensitive time for microbial colonization. During this period, helpful microbes support immune system maturity. By about age three, children usually have a more stable and diverse microbial community.

Newborns get microbes from the environment around them. Vaginal delivery tends to expose infants to maternal vaginal microbes. Cesarean delivery, or C-section, usually leads to more skin and environmental microbes. Researchers are studying whether exposing C-section newborns to maternal vaginal microbes could help reduce this difference.

Early feeding also shapes the infant gut. Breast milk contains oligosaccharides, which are special sugars that Bifidobacterium can use. These bacteria produce acetate and lactate, which help feed the infant and make the gut more acidic. A lower gut pH can slow the growth of harmful microbes. When infants move to formula or solid foods, Bifidobacteria often decline and microbes such as Bacteroidota and Clostridia increase.

Over the first year, the infant gut becomes more complex. The microbiome shifts from a simple community to one with more genes for vitamin synthesis and energy production. Delivery method and early diet both affect this colonization. Vaginally delivered infants share more microbes with their mothers, including Bifidobacterium and Lactobacillus. Formula feeding is linked with species such as Clostridium difficile, which may be potentially pathogenic.

By 12 months, the differences between delivery types become smaller, although C-section infants still tend to have more varied communities. Stopping breastfeeding, rather than starting solids, is what most strongly leads to an adult-like microbiota. In adulthood, the gut microbiome stays fairly stable over time, and Bacteroidota and Actinobacteria often persist the longest. Aging can shift this balance, often lowering Bacillota, which was formerly called Firmicutes, and reducing microbial diversity, especially in people living in institutions. Lower diversity in older adults is linked to frailty, which suggests that a varied microbiota may support health and longevity.

How Early Feeding Shapes the Gut Microbiota

how-early-feeding-shapes-the-gut-microbiota

introduction to the human microbiota

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Human microbiota are the microorganisms that live on and inside the body. They colonize the mouth, nasal passages, throat, stomach, intestines, urogenital tract, and skin. The total number of microbial cells may range from 10¹³ to 10¹⁴. That means microbes can match or even outnumber human somatic cells. This host-microbiome relationship has led scientists to describe humans as supraorganisms. In this view, microbial communities help shape development, immunity, and disease risk. Studying the...

The human microbiota starts forming at birth and changes as a person grows. The first years are a sensitive time for microbial colonization. During this period, helpful microbes support immune system maturity. By about age three, children usually have a more stable and diverse microbial community. Newborns get microbes from the environment around them. Vaginal delivery tends to expose infants to maternal vaginal microbes. Cesarean delivery, or C-section, usually leads to more skin and...

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development of the oral microbiota

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microbiota of the respiratory tract

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functions of the gut microbiota

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microbiota of the urogenital tract

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human virome

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key terms and concepts

See how birth mode and early feeding shape the gut microbiota, from breast milk and Bifidobacterium to adult stability and aging.

How Early Feeding Shapes the Gut Microbiota | JoVE K12

JoVE Core Microbiology provides an engaging introduction to the microbial world and its influence on health, industry, and the environment. This comprehensive collection covers key concepts such as microbial structure, metabolism, genetics, and ecology. It introduces essential laboratory techniques and microscopy methods through visually engaging animations. Corresponding scientist-in-action videos bridge classroom concepts with real-world research and applications.

microbiology

How Early Feeding Shapes the Gut Microbiota

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