Page 72 - Petelin Ana. Ur. 2022. Zdravje otrok in mladostnikov / Health of children and adolescents. Proceedings. Koper: Založba Univerze na Primorskem/University of Primorska Press
P. 72
avje otrok in mladostnikov | health of children and adolescents 72 Complementary feeding
According to the WHO definition, the introduction of CFs is needed to ensure
optimal energy and nutrient intake when ‘‘breast milk alone is no longer suf-
ficient to meet the nutritional requirements in terms of energy and nutrients
of infants’’ (World Health Assembly, 2002). Based on the available evidence,
current guidelines recommend that CFs (solids and liquids other than breast
milk or infant formula) should not be introduced before 4 months (17 weeks)
but should not be delayed beyond 6 months (26 weeks). GI and renal functions
are sufficiently mature by approximately 4 months to enable term infants to
process CFs, and by 4 to 6 months they will have attained the necessary mo-
tor skills to cope safely with CFs (Fewtrell et al., 2017). The introduction of CF
is this time frame is also regarded as the most appropriate in terms of health
outcomes. Conversely, the introduction before the age of 17 weeks is associated
with greater risk of obesity and adoption of unhealthy eating habits (D’Auria
et al., 2020). There may also be an increased risk of allergy if solids are intro-
duced before 3 to 4 months. There is, however, no evidence that delaying the in-
troduction of allergenic foods beyond 4 months reduces the risk of allergy, ei-
ther for infants in the general population or for those with a family history of
atopy (Fewtrell et al., 2017).
Infant’s gut microbiota
Until recently, it was widely believed that the microbial colonization of the GI
tract begins during and immediately after birth. However, the detection of bac-
teria in placental tissue and meconium suggests the first contact of the GI tract
with the microbiota already during pregnancy (Aagaard et al., 2014). More ex-
tensive colonization of the GI tract then occurs during and after birth, while
development and maturation of the microbiota are strongly influenced by var-
ious factors such as gestational age, mode of delivery (vaginal birth vs. birth by
caesarean section), nutrition (breast milk vs. milk formula), environment, and
antibiotic treatment (Zhuang et al., 2019). Among these factors, vaginal deliv-
ery and breastfeeding were found to positively modulate the composition of
the gut microbiota, while both contribute to an enrichment of beneficial bac-
terial strains such as Bifidobacterium (Martin et al., 2016). Moreover, higher
abundance of potentially pathogenic and proinflammatory Klebsiella and En-
terococcus in infants born with caesarean section may imply a higher risk of
immunological disorders and risk of infections (Reyman et al., 2019). In ad-
dition, pregnancy outcome and child development may also be influenced by
the microbial compounds and metabolites of the maternal microbiota (Roma-
no-Keeler & Weitkamp, 2015). The gut microbiota of the newborn is therefore
characterized by a high inter-individual diversity, which is generally low in the
first year of life, changes very rapidly and is shaped toward an adult-like be-
tween the age of 3 and 5 (Koenig et al., 2011).
According to the WHO definition, the introduction of CFs is needed to ensure
optimal energy and nutrient intake when ‘‘breast milk alone is no longer suf-
ficient to meet the nutritional requirements in terms of energy and nutrients
of infants’’ (World Health Assembly, 2002). Based on the available evidence,
current guidelines recommend that CFs (solids and liquids other than breast
milk or infant formula) should not be introduced before 4 months (17 weeks)
but should not be delayed beyond 6 months (26 weeks). GI and renal functions
are sufficiently mature by approximately 4 months to enable term infants to
process CFs, and by 4 to 6 months they will have attained the necessary mo-
tor skills to cope safely with CFs (Fewtrell et al., 2017). The introduction of CF
is this time frame is also regarded as the most appropriate in terms of health
outcomes. Conversely, the introduction before the age of 17 weeks is associated
with greater risk of obesity and adoption of unhealthy eating habits (D’Auria
et al., 2020). There may also be an increased risk of allergy if solids are intro-
duced before 3 to 4 months. There is, however, no evidence that delaying the in-
troduction of allergenic foods beyond 4 months reduces the risk of allergy, ei-
ther for infants in the general population or for those with a family history of
atopy (Fewtrell et al., 2017).
Infant’s gut microbiota
Until recently, it was widely believed that the microbial colonization of the GI
tract begins during and immediately after birth. However, the detection of bac-
teria in placental tissue and meconium suggests the first contact of the GI tract
with the microbiota already during pregnancy (Aagaard et al., 2014). More ex-
tensive colonization of the GI tract then occurs during and after birth, while
development and maturation of the microbiota are strongly influenced by var-
ious factors such as gestational age, mode of delivery (vaginal birth vs. birth by
caesarean section), nutrition (breast milk vs. milk formula), environment, and
antibiotic treatment (Zhuang et al., 2019). Among these factors, vaginal deliv-
ery and breastfeeding were found to positively modulate the composition of
the gut microbiota, while both contribute to an enrichment of beneficial bac-
terial strains such as Bifidobacterium (Martin et al., 2016). Moreover, higher
abundance of potentially pathogenic and proinflammatory Klebsiella and En-
terococcus in infants born with caesarean section may imply a higher risk of
immunological disorders and risk of infections (Reyman et al., 2019). In ad-
dition, pregnancy outcome and child development may also be influenced by
the microbial compounds and metabolites of the maternal microbiota (Roma-
no-Keeler & Weitkamp, 2015). The gut microbiota of the newborn is therefore
characterized by a high inter-individual diversity, which is generally low in the
first year of life, changes very rapidly and is shaped toward an adult-like be-
tween the age of 3 and 5 (Koenig et al., 2011).
