The nutritional adequacy of the food supply and promotion of healthy dietary habits are increasingly identified as major public health objectives to promote longer lives and a better quality of living throughout the life cycle. Minerals are particularly essential components of the diet. Minerals such as calcium and iron are needed for many biological reactions within the body and adequate intakes are essential to maintain optimum health. Despite the key role of minerals in human physiology, numerous questions exist on the ability of individuals to modify mineral metabolism during periods of increased nutrient demand, mineral deficiency or disease. To promote health and the prevention of disease, more information is needed on human nutrient metabolism particularly in vulnerable human groups such as infants, children and pregnant and lactating women. This knowledge will result in more accurate and scientifically informed nutrition and agriculture policies for public health benefit. The current state-of-the-art method utilized to study mineral metabolism in humans involves administration of naturally occurring, stable mineral isotopes and analysis of these isotopes using isotope ratio mass spectrometry. Our laboratory utilizes this approach for biomedical studies in human populations across many physiological conditions with an emphasis on the role of mineral intake in promotion of bone health and prevention of anemia.

Many minerals, such as calcium and iron, are consumed in suboptimal amounts by large segments of the U.S. population and are frequently limiting in developing countries. Failure to fully mineralize the developing skeleton can impact bone health and the subsequent risk of osteoporosis and fracture. Iron deficiency is the most common nutrient deficiency in the world. During pregnancy, calcium and iron deficiency can adversely impact both maternal and fetal birth outcomes. Pregnant adolescents are particularly vulnerable because intake must be sufficient to accommodate both maternal and fetal growth. More information is needed regarding the ability of adolescents to modify mineral metabolism and transfer of minerals to the fetus in response to early childbearing. Data on these topics will inform nutritional intake recommendations and increase the information available on human nutrient dynamics in vulnerable human populations.

Research in the Metabolic Mass Spectrometry lab, located in Cornell’s Human Metabolic Research Unit, focuses on mineral metabolism and bone health in infants, children, and pregnant and lactating women from both developed and developing countries. To address issues of calcium metabolism, we have undertaken metabolic studies in groups including children from osteoporotic families, pregnant and lactating adolescents, and children with chronic diseases such as cystic fibrosis and HIV infection. Current research focuses on the impact of adolescent pregnancy, particularly among minority populations, on maternal and fetal bone health, the risk of anemia, vitamin D insufficiency, birth outcomes, and determinants of adolescent weight gain across pregnancy. Partitioning of nutrients between the mother and fetus is also being addressed at the cellular level by assessing placental mineral transporters in relation to maternal and neonatal status. Our mass spectrometry laboratory includes instrumentation for high-sensitivity mineral stable isotope analysis, facilitating studies of mineral dynamics and bone calcium turnover. In addition to this work, our laboratory also collaborates with and provides analytical services to other academic institutions in the country, and is a collaborating site for NASA’s space flight research on bone health.

Findings from our research have been used to better inform nutritional recommendations and dietary guidelines for the intake of calcium and iron in both healthy and chronically ill populations. These results have focused attention on subgroups of the U.S. population that are at increased risk for deficiencies of nutrients such as iron and calcium, and the effects of these deficiencies on birth outcomes and maternal health across pregnancy.

nutrition / mineral metabolism