Young women who took an iron supplement for 16 weeks significantly improved their attention, short-term and long-term memory, and their performance on cognitive tasks, even though many were not considered to be anemic when the study began, according to researchers at Pennsylvania State University.

The study was the first to examine the impact of iron supplementation on cognitive functioning in women aged 18 to 35 (average age 21). Dr Laura Murray-Kolb says the study shows that even modest levels of iron deficiency have a negative impact on cognitive functioning in young women. She says the study also is the first to demonstrate how iron supplementation can reverse this impact in this age group.

Baseline cognition testing was performed on 149 women who classified as either iron sufficient, iron deficient but not anemic, or anemic. The women were then given either 60 mg (elemental) iron supplementation or placebo treatment for four months. At the end of that period, the 113 women remaining in the study took the same task again.

On the baseline test, women who were iron deficient but not anemic completed the tasks in the same amount of time as iron sufficient women of the same age, but they performed significantly worse. Women who were anemic also performed significantly worse, and in addition, they took longer to complete the tasks. The more anemic a woman was, the longer it took her to complete the tasks. However, supplementation and the subsequent increase in iron stores markedly improved cognition scores (memory, attention, and learning tasks) and time to complete the task.

This finding has great implications, says Dr. Murray-Kolb, because the prevalence of iron deficiency remains at 9% to 11% for women of reproductive age and 25% for pregnant women.

Federation of American Societies for Experimental Biology, Apr 19, 2004