The study – published in the Journal of Epidemiology and Community Health – examined the association between serum levels of vitamin D2 and D3 and academic performance in children after previous research had linked high vitamin D status to boosted cognitive functions in adults.
Led by Professor Debbie Lawlor from the University of Bristol, UK, the research team followed more than 3000 children from birth until their mid-teens – reporting that levels of serum 25-hydroxyvitamin D3 and D2 did not correlate with academic performance throughout childhood and adolescence.
“Despite biological evidence that variation in vitamin D and associated biomarkers might influence brain development and hence cognitive function, our prospective study suggests that neither 25(OH)D3 nor total 25(OH)D is an important determinant of academic performance in children and that 25(OH)D2 is actually inversely associated with performance,” wrote Lawlor and her colleagues.
The authors noted that previous research has linked high levels of the sunshine vitamin to enhanced brain functioning in adults.
“Higher total serum 25-hydroxyvitamin D (25(OH)D) concentrations have been associated with better cognitive function mainly in cross-sectional studies of adults. There are few prospective studies, and none of these are in children,” noted Lawlor and her team.
As a result, they wanted to find out if the same was true of children, and in particular what impact different forms of the vitamin – whether sourced mainly from sunlight (vitamin D3) or from plants (vitamin D2) – might have.
The prospective cohort study measured the serum 25(OH)D3 and 25(OH)D2 concentrations of 3171 children followed from birth at the age of 9. Academic performance was then measured at ages 13–14 years and 15-16 years by assessing total scores in English, mathematics and science (13-14) and performance in General Certificates of Education examinations (15-16).
The results showed that vitamin D3 levels were not associated with better academic achievement, whilst higher levels of vitamin D2 were actually linked to poorer performance in English in 13 to 14 year olds and fewer high grades at the ages of 15 and 16.
The authors say their findings back up other vitamin D research in children, and suggest that perhaps the benefits of the vitamin on adult brainpower don't emerge until later in life.