Micronutrient deficiencies occur all over the world but particularly in developing countries. Not all populations are equally at risk of each type of micronutrient deficiency: while iron deficiency anaemia may affect all countries, the likelihood of iodine and vitamin A deficiency varies from region to region. Special attention should therefore be given to population groups who come from areas of known specific deficiencies.
The most effective way to prevent micronutrient deficiency is to provide a diet that is diversified and includes fresh foods. For practical and logistic reasons, however, emergency food supplies usually consist of three or four basic items that are rarely changed and do not normally include fresh foods. A population that has to depend entirely on such a limited range of food items for more than 2 months runs the risk of developing nutritional deficiencies, especially scurvy (from lack of vitamin C) and pellagra (from lack of niacin).
There are several approaches to preventing onset of micronutrient deficiencies in emergency situations affecting large populations:
• Increasing the daily ration will allow a surplus to be sold for other purposes. It has been found that refugees receiving increased rations in fact consume a greater amount of fruit and vegetables;2 however, it would clearly be advisable to provide information to the households concerned, at the same time as rations, about micronutrient deficiencies and the importance of fruits and vegetables, so as to encourage the regular purchase of those foods.
• Varying the composition of the food basket, so that it contains more micronutrient-rich foods such as pulses (e.g. dried beans), groundnuts, fresh fruits and vegetables, and red palm oil. Pulses and groundnuts are easily obtainable. Fresh fruits and vegetables can be procured locally if they are readily (or potentially) available; if not, bringing them from a substantial distance is likely to be too costly. A better alternative is local production of fruits and vegetables in home gardens - this should be encouraged wherever agricultural conditions permit.
• Including micronutrient-fortified foods in the ration, e.g. cereals or cereal/pulse blends (see Annex 5) enriched with iron and/or vitamins A and B complex, iodized salt, vitamin A-enriched dried skim milk, or vegetable oils. Fortified products are considerably more costly than non-fortified ones and there has to be a trade-off: supplying more fortified products is likely to mean that a lesser total quantity of food is available.
• Providing supplementation when there is likely to be a specific deficiency, for instance when populations come from an area at known risk of that deficiency or are fed on a diet that is poor in particular micronutrients.
2 Hansch S. Diet and ration use in Central American refugee camps. Journal of refugee studies, 1992, 5(4): 300-312.
If clinical signs of deficiencies are already widespread, or if evaluation of dietary intake indicates specific deficiencies, the following measures are recommended:
• improving the diet by adding foods rich in the missing micronutrient(s), e.g. fresh vegetables and whole-grain processed cereals (ideally in ground form);
• supplementation with the missing micronutrient(s) until such time as the diet provides sufficient quantities to prevent deficiencies;
• when necessary, treatment of individuals with overt signs and symptoms of acute deficiencies.
The main clinical signs and symptoms of micronutrient deficiencies are summarized in Table 3.