Biofortified staple foods can contribute to body stores of iron, zinc, and vitamin A throughout the lifecycle, including those of children, adolescents, adult women, men, and the elderly. The benefits from biofortification are, however, not equal across all of these groups and depend on the amount of staple food consumed, the prevalence of existing micronutrient deficiencies, and the micronutrient requirement as affected by daily losses of micronutrient from the body and special needs for processes such as growth, pregnancy, and lactation. Some special considerations are as follows:
During pregnancy, maternal micronutrient needs are substantially increased. For iron, in particular, the requirement is so great the additional contribution from biofortification will be low. Additional means of meeting iron requirements during pregnancy will be required. A potentially more significant contribution of biofortification to women’s iron status is through improving her iron intake and status before entering pregnancy.
For iron and zinc, improved maternal nutritional status during pregnancy may also lead to increased transfer of iron and zinc to the fetus in late gestation. Infants are believed to rely on these stores for their iron and zinc requirements during the first 4-6 months of life.
Breastmilk vitamin A concentration decreases as a result of maternal vitamin A deficiency, and maternal consumption of provitamin A biofortified staple foods may help to maintain normal breast milk vitamin A concentrations. Therefore, all breastfed children, particularly those for whom breast milk provides a major source of total energy such as those up to 6 months of age, may benefit indirectly from biofortification with provitamin A due to increased intake of vitamin A from breast milk. Maternal iron or zinc status does not affect breastmilk content, so maternal consumption of iron and zinc biofortified foods is not expected to provide indirect benefits to the breastfed child.
Children between 6 and 23 months of age (and premature infants starting at 2 months) are particularly vulnerable to micronutrient deficiencies and are the most gravely affected by their irreversible consequences. Children less than 36 months of age consume relatively smaller amounts of staple foods and have relatively higher micronutrient requirements, compared to other older age groups. The contribution of nontargeted industrial fortification or biofortification (which both use food as a vehicle for augmenting nutrition) to the micronutrient adequacy in this vulnerable group will be relatively low in comparison with requirements, particularly for iron.
There are, however, exceptions. Due to the particularly high provitamin A content of several orange sweet potato varieties, regular consumption of these varieties can contribute substantially to vitamin A requirements of breastfed children 6-23 months of age.
