"Physicians should consider blood testing of female adolescents for iron deficiency within a few years of starting menses according to two studies by Penn State College of Medicine researchers. The researchers used data from more than  women  to  years old who took part in the National Health and Nutrition Examination Survey NHANES between  and . As part of the survey female participants had blood testing for iron deficiency as well as hemoglobin testing to identify anemia. Women are typically tested some time in their teens for anemia  the severe form of iron deficiency  using a quick and affordable hemoglobin test. However iron deficiency can develop years before anemia and can be missed by hemoglobin testing alone. If you think about your car you have to run your gas tank all the way down before the red light goes on and thats similar to the way were screening for iron deficiency said Deepa L. Sekhar physician and associate professor of pediatrics. Were basically waiting until their red light goes on. You have to be really low on your iron storage before youre going to flag as anemic. Iron deficiency without anemia has been associated with lower standardized math scores attention deficit disorder and restless leg syndrome in children and adolescents. Among irondeficient adolescent women there is a future risk of maternal iron deficiency and negative effects on infant health. Blood tests for iron deficiency without anemia have been developed but they are more costly and difficult to obtain in the doctors office compared to hemoglobin testing for anemia. Sekhar and colleagues hoped to determine risk factors for iron deficiency without anemia that could pinpoint which women could benefit most from this more costly testing. In the first study when the researchers analyzed the NHANES study data  percent of females who were  to  years old had iron deficiency without anemia. The researchers then looked at potential iron deficiency risk factors in this group including the age when they started menstruating as well as their race and ethnicity poverty status food insecurity tobacco or nicotine use dietary information body mass index BMI and physical activity. All of these factors have been associated with iron deficiency anemia in women in prior studies. However the only risk factor significantly associated with iron deficiency without anemia in young women in this study was having had a period for more than three years. The research was recently published in the journal PLOS ONE. In a second study the researchers next looked at whether a specially developed questionnaire could better predict iron status. Questions were included on depression poor attention and daytime sleepiness symptoms which all have been associated with iron deficiency or iron deficiency anemia but were not captured in the prior NHANES analyses. This questionnaire was compared to the currently recommended four iron deficiency anemiarisk questions in the Bright Futures Adolescent Previsit Questionnaire a survey recommended for physician use by the American Academy of Pediatrics. Ninetysix female adolescents participated in this study published in The Journal of Pediatrics. The Bright Futures questions alone did not predict iron deficiency or anemia. Yet the researchers risk assessment questionnaire was equally poor. Taken together the studies suggest that risk factors and assessments should not be used to determine which young women should receive testing for iron deficiency. The questions arent predictive Sekhar said. I think we need to establish the optimal timing for an objective assessment of adolescent iron deficiency and anemia. Sekhar believes the appropriate age may be  years old when most females will have been menstruating for at least three years. In addition to timing further research will be needed to determine which blood test for iron deficiency without anemia is accurate costefficient and practical for routine doctors office use. This test should be given with hemoglobin testing to catch all young women on the spectrum of iron deficiency Sekhar said. Iron deficiency can be corrected with dietary changes and supplementation Sekhar added. Other researchers on the study in PLOS ONE were Laura E. MurrayKolb in the Department of Nutritional Sciences Allen R. Kunselman in the Department of Public Health Sciences Carol S. Weisman in the Departments of Public Health Sciences and Obstetrics and Gynecology and Ian M. Paul in the Departments of Pediatrics and Public Health Sciences all at Penn State. This research received  of federal funding from The Eunice Kennedy Shriver National Institute of Child Health and Human Development of the National Institutes of Health grant number KHD which funded  percent of the project. MurrayKolb and Paul also worked on the study in The Journal of Pediatrics along with Eric W. Schaefer a biostatistician in the Department of Public Health Sciences. Nongovernment funding from Sackler Institute for Nutrition Science of the New York Academy of Sciences provided  percent of funding for this research project."