High Dose Vitamin D Supplementation Is Associated to An Improvement in Cognitive Abilitiy, Insomnia and Day-Time Sleepiness Among Adolescent Girls

Abstract

Objective: Vitamin D may be associated to the modulation of signaling cascade in the central nervous system. We aimed to evaluate the effect of high dose vitamin D supplementation on neuropsychological function in female adolescents. Methods: We evaluated the effects of 9 weeks of vitamin D supplementation [50000 IU of vitamin D3 (cholecalciferol)/weekly] on cognitive ability and sleep disorders among 940 adolescent girls. Results: Oral vitamin D supplementation upgraded cognitive abilities tasks including memory, inhibitory control and selective attention, decision making, planning, sustained attention and cognitive flexibility in healthy adolescent girls (p<0.001). The prevalence of subjects with insomnia after intervention fell from 15.0% to 11.3%. Similar results were also found for prevalence of subjects with sleepiness (15.6% decreased to 14.7%), or having cases with both insomnia and sleepiness (8.0% decreased to 6.1%; P<0.05). Conclusion: High dose vitamin D can improve cognitive abilities and ameliorated insomnia and daytime sleepiness among adolescent girls. Further investigations are needed on a various population group (age and gender) and to establish the sustainability of these effects. The significance of vitamin D therapy in other neurological diseases would also be of interest.