Pediatric Nutrition in Practice

114 Koletzko

introduced. In infants with a positive family his-
tory of allergy who are not exclusively breastfed,
the use of infant formulae based on hydrolyzed
cow’s milk proteins reduces the risk of atopic ec-
zema. Delayed introduction of complementary
feeding has no proven benefit.

Maternal Diet and Avoidance of Allergenic
Foods during Pregnancy and Lactation

Maternal dietary allergen exclusion during preg-
nancy has been proposed as a potential strategy
for reducing allergy risk in the offspring, but the
available data do not support any beneficial ef-
fects [1]. In human milk, food antigens derived
from cow’s milk, egg, wheat and other foods can
be detected a few hours after maternal consump-
tion of the respective foods. The concentration of
cow’s milk protein in breast milk is found to be
100,000 times lower than that in cow’s milk and
does not correlate with the amount of antigen in-
gested by the mother. Whether these low amounts
of antigen in breast milk induce sensitization or
tolerance is not clear. In a randomized controlled
trial, no beneficial effect of avoidance of egg and
milk consumption by lactating women was found
with regard to the development of allergic disease
in children up to 5 years of age [2]. Maternal ex-
clusion diets bear the risk of inadequate supply of
certain nutrients. In the absence of beneficial evi-
dence, maternal exclusion diets during pregnan-
cy and lactation for allergy prevention are not rec-
ommended. However, there is some evidence that
consumption of oily fish by the mother during
pregnancy and breastfeeding reduces the risk of
allergic diseases in the offspring [3].

Breastfeeding

Breastfeeding is preferred for infants because of
its nutritional, immunological and psychological
benefits. The potential allergy-preventive effect of

exclusive or partial breastfeeding has not been

properly assessed because randomization of

breastfeeding is not possible for ethical reasons.

Mothers who breastfeed exclusively differ mark-

edly from those who feed formula with regard to

education, socioeconomic factors, smoking,

keeping pets at home, introduction of other foods,

and many other factors which may influence the

incidence of allergy. Inverse causality may occur

in nonrandomized studies, i.e. mothers of infants

with the highest degree of heredity or signs of at-

opy within the first months of life may tend to

prolong exclusive and total breastfeeding.

However, evidence from a cluster randomized

trial of the promotion of breastfeeding in the Re-

public of Belarus [4] and from a recent meta-anal-

ysis of the effect of breastfeeding on allergy in the

offspring support that exclusive breastfeeding for

3 months or longer confers a protective effect

against atopic dermatitis during infancy [5].

Feeding Hydrolyzed Infant Formulae

Several intervention trials evaluated infant for-

mulae based on partially or extensively hydro-

lyzed proteins compared with standard cow’s

milk formula, often with nonrandomized breast-

fed reference groups. All randomized trials pub-

lished were performed on infants with an in-

creased atopy risk, based on one parent or sibling

affected by allergy, both parents affected, elevated

cord blood IgE or other criteria. Therefore, the

results cannot be generalized to infants with non-

atopic parents. Some of the studies included ad-

ditional cointerventions such as maternal dietary

or environmental restrictions, or delayed intro-

duction of complementary feeding.

A recent Cochrane review on these studies

concluded that there is limited evidence that the

use of hydrolyzed formulae reduces the risk of in-

fant and childhood allergy and infant cow’s milk

allergy when compared with using a standard

cow’s milk formula [6]. In this analysis, many

Koletzko B, et al. (eds): Pediatric Nutrition in Practice. World Rev Nutr Diet. Basel, Karger, 2015, vol 113, pp 113–117

DOI: 10.1159/000360328