الفهرس 
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Abstract
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Summary
Iron deficiency (ID) is the most common single-nutrient deficiency
in the world. In many low- and middle-income countries, the prevalence
of iron- deficiency anemia (IDA) among children under 5 years of age is
at least 25%, and is often higher.
The major causes of iron deficiency include inadequate
dietary iron intake due to consumption of a diet with low overall iron
content, or one that contains inhibitors of iron absorption, and
increased losses of iron because of chronic blood losses, most
commonly due to intestinal hookworm infection.
Poor dietary intake and limited bioavailability (the quantity or
fraction of the iron consumed that is absorbed and utilized) is considered
a major contributor to the global burden of iron deficiency. Populations
consuming diets that chiefly comprise cereals such as maize, wheat
and rice, with an inadequate intake of iron-rich foods, in particular
meat, but also legumes, nuts and other vegetables, are at high risk of
iron deficiency. Cereals (including maize) contain phytates which
bind to iron and prevent its absorption in the intestine .
Also, iron deficiency is most likely to occur during times
of increased iron requirements, and thus ID is seen most commonly in
infants and young children when rapid growth results in expansion of the
blood volume and an increase in iron requirements for production of red
blood cells.
Iron deficiency is associated with considerable morbidity across
the life cycle. In preschool children, iron deficiency anemia appears
to be associated with potentially irreversible impairments in cognitive
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development, and in school-aged children iron deficiency anemia is
associated with reduced school learning and educational performance.
In addition to direct effects on brain function, iron deficiency and
iron deficiency anemia may also affect child development indirectly
through non-responsive mother-child interactions.
Maternal iron deficiency is a global problem that may contribute
to high rates of maternal depression and non-responsive care-giving.
Intervention trials illustrate that children benefit from both nutritional
intervention and early learning interventions that promote responsive
mother-child interactions.
Iron deficiency anemia produces many systemic abnormalities:
blue sclerae, koilonychia, impaired exercise capacity, irritability, atrophic
glossitis, and an increased susceptibility to infection. Abnormal
developmental performance and poor growth are particularly important
features.
The diagnosis of iron deficiency is based primarily on laboratory
measurements. However, the tests used commonly have limitations due to
their poor sensitivity or specificity, or because they are modified by
conditions other than iron deficiency (such as inflammation).
So, combining several iron status indicators provides the best
assessment of iron status. Important laboratory indicators for evaluating
the iron status include Evaluation of multiple indicators such as soluble
transferrin receptors (sTfRs), sTfR–ferritin index (sTfR–F), zinc
protoporphyrin / heme ratio (ZPP/H), reticulocyte hemoglobin (Hb)
content (CHr) , ferritin, and transferrin/total iron binding capacity.
Bone marrow examination for macrophage iron is considered a
gold standard for diagnosis of iron deficiency, but it is rarely performed
in field studies.
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Hepcidin (iron regulatory hormone secreted by liver) concentration
reflects body iron, so, the ability to measure plasma or urinary hepcidin
could potentially become the single most important test for monitoring
iron status. However, progress in developing a simple, inexpensive and
widely available hepcidin assay has been slow.
Prevention of iron deficiency anemia during pregnancy has been
associated in some studies with alleviation of low birth weight (which in
turn is associated with reduced infant iron endowment and a subsequent
increased risk of iron deficiency anemia. Maternal iron deficiency is
global problem that may contribute to high rates of maternal depression
and non-responsive care giving.
Children can benefit from both nutritional interventions and early
learning interventions that promote responsive mother-child interactions.
Strategies to improve iron intake include improving over all dietary
diversity, supplementation, point of use fortification of foods with
micronutrient powders and fortification of staple foods with iron.
Increasing the availability and consumption of a nutritionally
adequate diet is the only sustainable and long-term solution, not just for
overcoming iron deficiency and anemia, but for overcoming other
micronutrient deficiencies as well.
Food-based approaches include increasing overall food intake,
increasing consumption of micronutrient-rich foods, modifying intake of
dietary iron inhibitors and enhancers, using improved processing,
preservation and preparation techniques, consumer education for
behaviour change, improving food quality and safety and public health,
and food fortification.