Research Interests Dr. Lönnerdal's research program is focused on two main areas: infant/pediatric nutrition and trace element metabolism. Current research topics include: Studies on factors affecting breast milk composition, including maternal nutrition, hormones and stage of lactation Mechanisms for nutrient uptake by mammary cells as well as expression of genes encoding human milk proteins Bioavailability of nutrients to infants and how this is affected by the mode of feeding, including receptor-mediated uptake mechanisms in the small intestine Iron, zinc, copper and selenium nutrition of infants, children and adolescents Bioactive factors in milk Trace element uptake and transport by biological membranes, including receptor-mediated uptake of trace elements by the placenta, intestine, liver and mammary gland Nutrient-nutrient interactions