Ian J. Griffin, M.D., B.S.
Assistant Professor of Pediatrics
Baylor College of Medicine
Section of Neonatology
Texas Children's Hospital
Globally, the four most important micronutrient
deficiencies are iron, vitamin A, zinc and iodine.
My research is based on the use of stable isotopes to study the metabolism of two of these micronutrients, iron and zinc, in children. Unlike radio-isotopes, stable isotopes are safe for use in children and pregnant women, and for repeated studies. However, the analysis of stable isotopes is costly and complicated. The stable isotope laboratory at the Children's Nutrition Research Center is one of the few facilities able to do such analysis, housing two mass spectrometers - a Thermal Ionization Magnetic Sector Mass Spectrometer (TIMS) and a High Resolution Induction Couples Plasma Mass Spectrometer (ICP-MS) capable of such analysis.
Recently, enormous interest has centered on the biological role of zinc. It has a vital role both in cell proliferation and apoptosis (programmed cell death), and immune function. Research on zinc requirements are hindered by the lack of any simple measure of zinc status. We have done several studies examining the role of compartmental modeling (a mathematical description and simplification of in vivo metabolism) or the exchangeable zinc pool (a very simplified measure of zinc metabolism) as an assessment of zinc status. Compartmental modeling also allows a more complete understanding of zinc metabolism. We have studied both healthy subjects and those with Crohn's disease, and shown stereotyped changes in both situations.
We have also collaborated in several studies in developing countries examining the bioavailability of minerals from fortified foods. These include studies in Mexico of calcium absorption from fortified foods, and studies in Indonesia on iron and zinc from fortified flour and the possible adverse effect of zinc supplementation on iron absorption.
Abrams SA, Griffin IJ, Hawthorne KM, Gunn SK, Gundberg CM, Carpenter TO. Relationships among vitamin D levels, parathyroid hormone, and calcium absorption in young adolescents. J Clin Endocrinol Metab. 90(10):5576-5581, 2005.
Abrams SA, Griffin IJ, Hawthorne KM, Liang L. Height and height Z-score are related to calcium absorption in five- to fifteen-year-old girls. J Clin Endocrinol Metab. 90(9):5077-5081, 2005.
Abrams SA, Griffin IJ, Hawthorne KM, Liang L, Gunn SK, Darlington G, Ellis KJ. A combination of prebiotic short- and long-chain inulin-type fructans enhances calcium absorption and bone mineralization in young adolescents. Am J Clin Nutr. 82(2):471-476, 2005.
Chen Z, Griffin IJ, Plumlee LM, Abrams SA. High resolution inductively coupled plasma mass spectrometry allows rapid assessment of iron absorption in infants and children. J Nutr. 135(7):1790-1795, 2005.
Abrams SA, Griffin IJ, Hawthorne KM, Chen Z, Gunn SK, Wilde M, Darlington G, Shypailo RJ, Ellis KJ. Vitamin D receptor Fok1 polymorphisms affect calcium absorption, kinetics, and bone mineralization rates during puberty. J Bone Miner Res. 20(6):945-953, 2005.
Griffin IJ, Abrams SA. Methodological considerations in measuring human calcium absorption: relevance to study the effects of inulin-type fructans. Br J Nutr. 93 Suppl 1:S105-S110, 2005.
Rosado JL, Diaz M, Gonzalez K, Griffin I, Abrams SA, Preciado R. The addition of milk or yogurt to a plant-based diet increases zinc bioavailability but does not affect iron bioavailability in women. J Nutr. 135(3):465-468, 2005.
Perez-Exposito AB, Villalpando S, Rivera JA, Griffin IJ, Abrams SA. Ferrous sulfate is more bioavailable among preschoolers than other forms of iron in a milk-based weaning food distributed by PROGRESA, a national program in Mexico. J Nutr. 135(1):64-69, 2005.
Griffin IJ, Hicks PD, Liang LK, Abrams SA. Metabolic adaptations to low zinc intakes in premenarcheal girls. Am J Clin Nutr. 80(2):385-390, 2004.
Hawthorne KM, Griffin IJ, Abrams SA. Current issues in nutritional management of very low birth weight infants. Minerva Pediatr. 56(4):359-372, 2004.
Griffin IJ, Kim SC, Hicks PD, Liang LK, Abrams SA. Zinc metabolism in adolescents with Crohn's disease. Pediatr Res. 56(2):235-239, 2004.
Avalos Mishaan AM, Zavaleta N, Griffin IJ, Hilmers DC, Hawthorne KM, Abrams SA. Bioavailability of iron and zinc from a multiple micronutrient-fortified beverage. J Pediatr. 145(1):26-31, 2004.
Abrams SA, Griffin IJ, Hicks PD, Gunn SK. Pubertal girls only partially adapt to low dietary calcium intakes. J Bone Miner Res. 19(5):759-763, 2004.
Shah M, Griffin IJ, Lifschitz CH, Abrams SA. Effect of orange and apple juices on iron absorption in children. Arch Pediatr Adolesc Med. 157(12):1232-1236, 2003.
Chen Z, Griffin IJ, Kriseman YL, Liang LK, Abrams SA. Inductively coupled plasma mass spectrometric analysis of calcium isotopes in human serum: a low-sample-volume acid-equilibration method. Clin Chem. 49(12):2050-2055, 2003.
Abrams SA, Mushi A, Hilmers DC, Griffin IJ, Davila P, Allen L. A multinutrient fortified beverage enhances the nutritional status of children in Botswana. J Nutr. 133(6):1834-1840, 2003.
Griffin IJ, Abrams SA. Zinc absorption by infants. Minerva Pediatr. 55(3):231-242, 2003.
Griffin IJ, Abrams SA. Methodological issues in stable isotope-based kinetic studies in children. Adv Exp Med Biol. 537:117-130, 2003.
S Herman, IJ Griffin, S Suwartil, F Ernawati, SA Abrams. Co-fortification of iron fortified flour with zinc sulfate, but not zinc oxide, decreases iron absorption in Indonesian children. Am J Clin Nutr 2002; 76:813-7.
IJ Griffin, JC King, SA Abrams. Body weight specific zinc compartmental masses in children significantly exceed those reported in adults: a stable isotope study, and an expanded kinetic model. J Nutr 2000; 130:2607-12.
IJ Griffin, RJ Cooke, MM Reid, KPB McCormick, JS Smith. Iron nutritional status in preterm infants fed fortifiedformulas fortified with iron. Arch Dis Child 1999; 81:F45-49.
Faculty Web Pages