Pediatric Nutrition in Practice

148 Saleem  Bhutta

Global Micronutrient Deficiencies:
Perspective of Developing Countries

Women of child-bearing age, infants and chil-
dren are at high risk of micronutrient deficiencies
or malnutrition in developing countries. Four
micronutrients (vitamin A, zinc, iron and iodine)
have been directly or indirectly associated with
about 12% of deaths among <5-year-old children
globally [1, 2]. Other manifestations associated
with micronutrient deficiencies (i.e., iron and
zinc) not only affect birth weight and lead to birth
defects but also impact child growth as well as
later cognitive and reproductive performance.
Vitamin A deficiency (VAD) is associated with
xerophthalmia, corneal xerosis, ulceration and
keratomalacia, and vitamin D deficiency leads to
rickets and osteomalacia. Micronutrient deficien-
cies directly and/or indirectly affect learning and
adult productivity, thus impacting economic
growth in terms of premature deaths and loss of
healthy lives as expressed in disability-adjusted
life years ( table 1 ).
A need to strengthen our efforts and sharpen
our focus, concentrating efforts on the crucial
period of pregnancy and the first 2 years of life –
the 1,000 days from conception to a child’s sec-
ond birthday – has gained wide acceptance. This
is the time period in which good nutrition and
healthy growth not only can have lasting benefits
for individuals but also may be important for the
economic productivity of a society [1].

Iron and Anemia

Iron deficiency anemia (IDA) is the most preva-

lent form of nutritional anemia. It accounts for

approximately half of the global anemia cases

and poses an increased risk of maternal and

child mortality [2, 6]. Multiple risk factors in-

cluding poor dietary intake of iron, high intake

of fibers from cereal and legumes, low birth

weight, infections and poverty contribute to

IDA. A Cochrane review of daily iron supple-

mentation to women during pregnancy reported

a 19% reduction in the incidence of low birth

weight [7, 8].

The cognition of children aged ≥ 5 years with

IDA generally benefited from iron supplementa-

tion, but studies of children <3 years of age have

had mostly negative findings, except for delayed

brain maturation [1, 9, 10]. The role of iron sup-

plementation on mental development has been

questioned in the past. Black et al. [1] reviewed

7 double-blind randomized controlled trials

of iron supplementation lasting ≥ 8 weeks to

c h i ld re n <4 ye a r s of a ge. Fi ve t r i a l s s howe d b e ne -

fits in motor development, 1 showed a benefit

in language; however, there is no convincing

evidence that iron treatment had an effect on

mental development in children <27 months of

age [8].

It is also important to note that in resource-

poor settings, low levels of other micronutrients

(vitamin A, zinc, calcium, ribof lavin and vitamin

Ta b l e 1. Global deaths attributed to micronutrient deficiencies as well as disability-adjusted life

years (DALYs) of children <5 years of age [23]

Deaths % of deaths in

children <5 years

Disease burden,

1,000 DALYs

% of DALYs in

children <5 years

Vitamin A deficiency 667,771 6.5 22,668 5.3

Zinc deficiency 453,207 4.4 16,342 3.8

Iron deficiency 20,854 0.2 2,156 0.5

Iodine deficiency 3,619 0.03 2,614 0.6

Koletzko B, et al. (eds): Pediatric Nutrition in Practice. World Rev Nutr Diet. Basel, Karger, 2015, vol 113, pp 147–151

DOI: 10.1159/000375276