High folate intake is related to better academic achievement in Swedish adolescents

Adolescents are vulnerable to increased plasma total homocysteine (tHcy) and to insufficient folate status. Folate status and Hcy metabolism are linked to cognitive functions, but academic achievement by adolescents has not been studied in this respect. To assess a possible link between academic achievement in adolescents and tHcy and its determinants, dietary folate intake, MTHFR 677 TT homozygosity, and socioeconomic status (SES). A study of 386 Swedish adolescents aged 15 years in whom plasma tHcy and MTHFR 677C →T genotype were assayed. The sum of school grades in 10 core subjects obtained in the final semester of compulsory 9 years of schooling was used as outcome measure of academic achievement. Lifestyle and SES data were obtained from questionnaires. Academic achievement was strongly correlated to tertiles of tHcy (negatively; P = .023) and to tertiles of folate intake (positively; P < .001). Other significant predictors were gender, smoking, and SES (proxied by school, mother's education, and father's income). When these were controlled for, tertiles of folate intake (P < .002) but not tertiles of tHcy (P = .523) or MTHFR genotype remained significantly related to academic achievement. Folate intake had a positive association with academic achievement in the 15-year-olds, which was not attenuated by SES or MTHFR 677 TT homozygosity. These results provide new information that points to the importance of keeping a closer watch on folate status in childhood and adolescence. They may also have direct implications for school meal provisions, school teaching programs, and information to parents.