Pediatric Nutrition in Practice

1 Specific Aspects of Childhood Nutrition

Key Words

Microbiota · Probiotics · Prebiotics · Health

Key Messages

• A healthy microbiota preserves and promotes host
  wellbeing and absence of disease in general – not
  only in the gastrointestinal tract


• Colonization of the infant by microbes is initiated
  during pregnancy


• Initial colonization by ‘pioneer bacteria’ is en-
  hanced by both naturally occurring bacteria and
  oligosaccharides in breast milk


• These pioneer bacteria direct later microbiota suc-
  cession, forming a basis for a healthy gut microbio-
  ta throughout one’s lifetime


• The microbiota resembles that of adults by 2–3
  years of age


• Disturbed microbiota succession during early in-
  fancy has been linked to increased risk of infectious,
  inflammatory and allergic diseases later in life


• Intestinal microbial colonization and its modula-
  tion by dietary means are important considerations
  during the first years of life
  © 2015 S. Karger AG, Basel

Initial Establishment of Microbiota

Source of Original Microbiota

The microbiota of a newborn is acquired from the

mother before and after birth and develops rapidly

following delivery. It is initially strongly depen-

dent on the mother’s microbiota, the mode of de-

livery and the birth environment [1, 2]. The micro-

biota of the mother is determined by genetic and

environmental factors. Stress and dietary habits

during later pregnancy have a significant impact

on the microbiota. Even in healthy pregnancy, the

maternal microbiota changes considerably be-

tween the 1st and the 3rd trimester [3]. Such

changes influence the quality and quantity of the

initial colonizers of the newborn. Subsequently,

feeding practices (formula or human milk) and the

infant’s home environment influence microbiota

succession at the genus and species level, as well as

species composition and numbers of bacteria.

Succession of Microbial Communities

Establishment of the microbiota in the newborn

occurs in a stepwise fashion. Studies on mice have

shown that the first bacteria to colonize the intes-

tine, even prior to delivery and during the perina-

tal period (‘pioneer bacteria’), can modulate gene

expression in host intestinal epithelial cells. This

Koletzko B, et al. (eds): Pediatric Nutrition in Practice. World Rev Nutr Diet. Basel, Karger, 2015, vol 113, pp 87–91
DOI: 10.1159/000360322

1.8 Gut Microbiota in Infants

Akihito Endo  Mimi L.K. Tang  Seppo Salminen

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