Nutritional care of premature infants: microminerals

Microminerals, including iron, zinc, copper, selenium, manganese, iodine, chromium and molybdenum, are essential for a remarkable array of critical functions and need to be supplied in adequate amounts to preterm infants. Very low birth weight (VLBW) infants carry a very high risk of developing iron deficiency which can adversely affect neurodevelopment. However, a too high iron supply in iron-replete VLBW infants may induce adverse effects such as increased infection risks and impaired growth. Iron needs are influenced by birth weight, growth rates, blood losses (phlebotomy) and blood transfusions. An enteral iron intake of 2 mg/kg/day for infants with a birth weight of 1,500-2,500 g and 2-3 mg/kg/day for VLBW infants is recommended. Higher doses up to 6 mg/kg/day are needed in infants receiving erythropoietin treatment. Regular monitoring of serum ferritin during the hospital stay is advisable. Routine provision of iron with parenteral nutrition for VLBW infants is not recommended. Less certainty exists for the advisable intakes of other microminerals. It appears prudent to provide enterally fed VLBW infants with daily amounts per kilogram body weight of 1.4-2.5 mg zinc, 100-230 μg copper, 5-10 μg selenium, 1-15 μg manganese, 10-55 μg iodine, 0.03-2.25 μg chromium, and 0.3-5 μg molybdenum. Future scientific findings may justify deviations from these suggested ranges.