FOOD SECURITY - Science for Agriculture and Rural Development in Low-income Countries - page 35

supplementation of Vitamin A as pills or oil capsules. A diversified diet, with the
right composition for optimal absorption is the preferred intervention for solving the
Vitamin A problem. However, in times of food insecurity, a well-balanced and
diversified diet, containing expensive foods from animal origin or fruits and
vegetables is all but impossible.
Iron
Iron deficiency is probably the best-known and most common micronutrient
deficiency. An estimated 2 billion people, or one third of the world population, both
in developing and in developed countries, suffer from iron deficiency anemia (IDA).
It is often thought to be mainly a problem of women in the reproductive age, in
which it is indeed common, but IDA is also common in young children and is then
often associated with intestinal parasites. Almost 60% of the pregnant women and
one third of the young children (0-4 years) in developing countries suffer from IDA.
Of children 5-14 years of age, more than half suffer from IDA; of adult men and
women on average 43% (women) and 34% (men), respectively. IDA leads to
fatigue, reduced labour output, slower learning and concentration problems in school
children, and higher prevalence of maternal mortality.
Haem iron, the form of iron in the diet that is best absorbed by the human body,
naturally occurs in foods of animal origin, mainly in red meat. Iron also occurs in
foods of plant origin (green leafy vegetables, cereals), but its absorption is then often
limited by anti-nutritional factors present in these products, such as tannins. Dietary
habits influence bio-availability of iron in the diet: Drinking tea with a meal inhibits
iron absorption, because of the presence of tannins, Vitamin C (orange juice)
enhances iron absorption.
Interventions to reduce iron deficiency include recommendations for dietary
adaptations, supplementation (with daily or weekly supplements), fortification of
industrially produced foods, and, more recently, bio-fortification or 'breeding for
enhanced levels of micronutrients'. As for Vitamin A deficiency, a diversified and
well-balanced diet might be the 'ideal' solution. However, such a diet is relatively
expensive as it requires sizeable quantities of foods of animal origin (mainly meat
and fish), and fruits and vegetables containing Vitamin C to enhance iron absorption
and providing some iron themselves.
Iodine
Clinical symptoms of iodine deficiency are enlargement of the thyroid gland and the
development of (irreversible) goiter in more or less advanced stages. However, the
major problem is the high prevalence of babies born with physical and mental
retardation in populations living under conditions of iodine deficiencies. Iodine
deficiency in a woman during pregnancy can lead to the birth of a cretinous baby, a
child that appears normal at birth, but shows slow growth and development, possibly
never reaching normal length (dwarfism), being mentally retarded and sometimes
deaf-mute. Cretinism is the ultimate and most severe form of iodine deficiency.
Populations with lower or less severe levels of iodine deficiencies might show
reduced learning capabilities in the younger generation. Reductions in IQ up to
10-13 points have been documented.