Pediatric Nutrition in Practice

66 Solomons

tions between vitamins, between trace elements
and between vitamins and trace elements are rec-
ognized. These are quite common for vitamin A
with its interactions with vitamins D and E and
assorted elements such as iodine and iron [13].
The competition between iron and zinc is notable
for its potential consequences in public health in-
terventions [14].
Excessive exposure to certain vitamins and
virtually all of the trace elements can have ad-
verse effects on children. For 7 of the vitamins
and all of the inorganic elements, certain daily
dietary amounts pose the risk of the adverse con-

sequences of overload a nd even tox icit y i f exceed-

ed. These so-called upper tolerable intake levels

have been established by agencies such as the

Food and Nutrition Board of the USA and the

European Food Safety Authority. The interplay

between essential risks of dietary deficiency and

public health interventions to enhance the mi-

cronutritional status can lead to paradoxical situ-

ations. Increasingly, this also takes place at the

interface of the low nutrient content of the diet

selected and the sum of fortification and self-sup-

plementation sources. Table 4 illustrates a selec-

tion of these paradoxes.

Ta b l e 4. A listing of some pertinent paradoxical associations and precautions related to dietary

exposure to micronutrients

The tolerable upper intake levels for zinc in toddlers and preschool children may be too low,

as they are lower than the average amounts of zinc consumed by apparently healthy children

in the USA

The traditional ideal is that all members of a family unit share the majority of meals as a family.

In this regard, the tolerable upper intake level of preformed vitamin A for children under 6 years

is lower than the recommended daily intake of total vitamin A for pregnant or lactating women

in the same household

The currently recommended intake levels for vitamin D, especially for adolescents and for

individuals from darkly pigmented ethnic groups living in temperate latitudes such as Europe,

North America and southern Australia, may not be sufficient to maintain protective circulating

levels of the vitamin. Pediatric dermatologists and nutritionists are at odds about the value of

sun exposure. The dermatological community advocates maximal sunscreen protection to

avoid skin damage and malignancy risk, whereas pediatric nutritionists realize that maximizing

vitamin D formation in skin in temperate latitudes requires some relaxation of solar exposure

avoidance measures

An upward spiral of market-driven fortification, with multiple manufacturers adding micronutrients

to make their products more attractive and ‘nutritious’, runs the risk of providing child consumers

with several times the daily recommended amounts of some vitamins and minerals

Folic acid is a synthetic and totally oxidized form of folate. Folic acid fortification is mandated in

many countries for the prevention of neural tube defects in the pregnancies of susceptible

women. These higher folic acid intakes may have additional benefits for adults through the

prevention of stroke and vascular disease. However, in adults with established dysplastic

changes in the large bowel mucosa, higher folic acid exposure accelerates the progression to

colorectal cancer. Limited evidence for a similar scenario exists for prostatic neoplasia. We have

little understanding of these beneficial versus harmful effects for the pediatric population

Epidemiological evidence is accumulating that the consumption of preformed vitamin A from

animal sources and food fortification weakens bone mineralization. The extent and importance

of such a process in childhood merit research attention

Koletzko B, et al. (eds): Pediatric Nutrition in Practice. World Rev Nutr Diet. Basel, Karger, 2015, vol 113, pp 62–67

DOI: 10.1159/000367871