|Vol. 3, No. 3, 1997 Page 7|
Cognitive problems are strongly linked to delinquency, criminality, and behavior problems. In addition, cognitive deficits, and in particular weaknesses in language skills, play a role in drug and alcohol abuse (see related article, Crime Times, Vol. 2, No. 3, Page 3). But new research adds to evidence that cognitive skills, far from being unchangeable, can often be improved significantly through simple, inexpensive biological interventions.
Ann Bruner and colleagues recently studied the effects of iron supplementation on 73 high school girls who were deficient in iron, but not anemic. In a double-blind, placebo-controlled study, Bruner et al. gave iron supplements to 37 of the girls, while 36 took placebos. Blood tests and tests of cognitive functions were administered both before and after the study.
According to the researchers, iron concentrations more than doubled in the group taking supplements for eight weeks. When these girls' cognitive skills were tested following treatment, Bruner et al. say, "girls who received supplements... performed better on verbal learning and memory tasks than the girls who had not taken iron supplements." Bruner et al. conclude that "even in the absence of anemia, iron supplementation improves some aspects of cognitive functioning in iron-deficient adolescent girls."
The researchers note that iron deficiency is epidemic: despite the current fortification of cereals and other foods, as many as 25% of adolescent American girls have inadequate intakes of the nutrient. (Girls are more prone to iron deficiency than boys, because of iron lost during menstrual cycles.) "Animal models," Bruner et al. say, "have revealed several mechanisms by which iron deficiency may affect cognition; these include changes in brain iron content and distribution, and in neurotransmitter function."
Earlier research suggests that iron deficiency impairs not only cognitive skills, but also behavior. In 1992, researcher Melvyn Werbach reported that iron deficiency "has been shown to be directly associated with aggressive behavior (conduct disorder)," and Jun-bi Tu et al. reported in 1995 (see related article, Crime Times, Vol. 1, No. 4, Page 7) that iron treatment led to significant improvement in the behavior of two violent and destructive teens. An earlier study by G. M. Rosen et al. found that nearly a third of a population of incarcerated delinquents, most of them male, showed evidence of iron deficiency.
"Randomised study of cognitive effects of iron supplementation in non-anaemic iron-deficient adolescent girls," Ann B. Bruner, Alain Joffe, Anne K. Duggan, F. Casella, and Jason Brandt, The Lancet, Vol. 347, No. 9033, Oct. 12, 1996, pp. 992-996. Address not listed. -and- "Iron deficiency among incarcerated juvenile delinquents," G. M. Rosen, A. S. Deinard, S. Schwartz, C. Smith, B. Stephenson, and B. Grabenstein, Journal of Adolescent Health Care, Vol. 6, No. 6, 1985, pp. 419-423. Address not listed.