High Folate Intake Linked to Better Grades in Swedish Teens

Fran Lowry

July 15, 2011

July 15, 2011 — Swedish teenagers who are deficient in folate have poorer grades than teens who have a high folate intake, according to new research published online July 11 in Pediatrics.

The link between folate intake and academic performance is independent of socioeconomic status, senior author Torbjorn K. Nilsson, MD, PhD, professor of medicine at Örebro University, Örebro, Sweden, told Medscape Medical News.

"The effect of folate on academic performance was seen in the teens from higher-income brackets, as well as the lower, so the effect was not just explainable by socioeconomics, and that’s very important," Dr. Nilsson said.

Sweden is a country that does not allow foods to be fortified, he said. Milk, yogurt, and cheese make up the main source of folate in the diet in Sweden and other Scandinavian countries, and fruits and vegetables are other sources.

Dr. Torbjorn K. Nilsson

"We have a poor intake of folate compared to people in the US, our intake is below what is recommended daily. We do not achieve the recommended daily intake in Sweden," Dr. Nilsson noted.

People at both ends of the age spectrum are vulnerable to insufficient folate. Vitamin B deficiency can affect the risk for dementia in the elderly and be a cause of impaired neural development in infants, but little is known about the effect of folate on the cognitive development and academic achievements of teens.

To assess a possible link between academic achievement and folate intake in this population, the researchers studied 386 teens aged 15 years. The children were participants in the Swedish part of the European Youth Heart Study, which studies risk factors for future cardiovascular disease among children aged 9 to 10 and 15 to 16 years.

Blood samples were obtained and assayed for total homocysteine, a biomarker for folate intake, and mutations in the methylene tetrahydrofolate reductase (MTHFR) gene, which is known to raise levels of homocysteine.

The researchers also assessed smoking habits, parental education and income, and the effect of the individual school on grades.

Additionally, the children were interviewed and asked what they had eaten the day before.

The study found that teens in the lowest tertile of dietary folate intake had the poorest academic performance. Homocysteine levels were not associated with academic performance.

The association between folate intake and academic achievement was more pronounced in low-income families and in poorer-quality schools, but the lower-socioeconomic-status families were not the sole drivers of this observed effect, Dr. Nilsson noted.

"The benefit of good folate intake is highest for children coming from poor-income, low-education parents — that is the important clinical implication of this study. But the effect was seen in high-income, high-education families as well. So the implication from a public health level would be that everyone could use information related to food and health," he said.

Dr. Nilsson also feels that schools in Sweden might begin to provide folate-rich foods in snacks and meals.

Jatinder Bhatia, MD, from Georgia Health Sciences University, Augusta, Georgia, said that the study warrants follow-up with other studies in other populations.

"I find the study intriguing but I don’t think we can say that this is a cause-and-effect relationship," said Dr. Bhatia, who is also chair of the American Academy of Pediatrics Committee on Nutrition.

"To say that high folate intake possibly is associated with academic achievement is OK. I can buy that. But there are so many other important variables to consider. This is an intriguing study that needs more attention," he said.

Scott Drab, PharmD, from the University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania, agreed with the authors that low folate should be looked at in this particular population, especially because folate deficiency can be an issue in Sweden.

But, he noted, folate deficiency is not a problem in the United States. "We know that folate plays an important role in brain development and function, but here, the normal western diet is not folate deficient."

Dr. Drab also pointed out that supplementing folate can be dangerous.

"High folate intake from supplementation has actually been associated with the development of tumors. Folate is needed for DNA synthesis, and in rapidly dividing cells, like in pregnancy. That is the same thing that happens in cancers, too. So there’s a fine line here," he said.

"I think it certainly makes sense to look at folate deficiency, and that is what the author was getting at here. These results provide new information that points to the importance of keeping a closer watch on folate status in children, and it doesn’t say anything about folate supplementation, just to keep a closer watch, and I would agree with that. If I lived in an area that was deficient in folic acid, I think we would have to do that."

Dr. Nilsson, Dr. Bhatia, and Dr. Drab have disclosed no relevant financial relationships.

Pediatrics. Published online July 11, 2011.


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