Zinc-fortified foods may help seventh graders perform better in school, according to study findings presented at the Experimental Biology 2005 meeting in San Diego.

In a 10-week study of 209 seventh graders, those who consumed fruit juice supplemented with zinc cut their reaction time on a visual memory test by 12 percent compared with 6 percent for students who received regular juice.

They also had more correct answers on a word recognition test and had better scores on a task requiring sustained attention and vigilance.

However, test performance did not improve significantly in students who were already meeting recommended daily allowances for zinc intake.

If confirmed, these results may help fuel a review of recommended zinc intake guidelines for adolescents, Dr. James G. Penland from the Grand Forks Human Nutrition Research Center in North Dakota noted in a telephone interview with Reuters Health.

It’s important to remember that these results were achieved in a group of adolescents who were not zinc deficient, he emphasized. “So if we could see benefits from slightly increasing zinc intake in that group it bodes well for what we might find with a zinc deficient population,” he said.

“Adolescence is a critical period of rapid growth physically, emotionally and mentally. That coupled with the fact that zinc is one of the nutrients that adolescents do not consume in recommended amounts led us to this study,” Penland added.

Supplemental zinc did not appear to improve motor or psychosocial functioning in the current study, although conduct problems increased by 10 percent in girls who were given juice lacking zinc.