title: No association between serum 25-hydroxyvitamin D3 level and performance on psychometric tests in NHANES III.
abstract: BACKGROUND
  Animal studies and in vitro experiments indicate that vitamin D is involved in a diverse range of neurobiological functions. We had the opportunity to examine the relationship between serum 25-hydroxyvitamin D(3) [25(OH)D] levels and performance on various cognitive tasks, based on a large, representative community sample.
  
  
  METHODS
  Three age groups were available from the population-based NHANES III survey: adolescent group (n = 1,676, age range 12-17 years), adult group (n = 4,747, 20-60 years), elderly group (n = 4,809, 60-90 years). The associations between eight psychometric measures and serum 25(OH)D were assessed.
  
  
  RESULTS
  In the adolescent and adult groups, none of the psychometric measures were associated with 25(OH)D levels. In the elderly group there was a significant difference between 25(OH)D quintiles performance on a learning and memory task; however, those with the highest quintile of 25(OH)D were most impaired on the task, contrary to the hypotheses.
  
  
  CONCLUSIONS
  Lower 25(OH)D levels were not associated with impaired performance on various psychometric measures. While it remains to be seen if chronic exposure to low 25(OH)D levels alters brain function in the long term, this cross-sectional study suggests that 25(OH)D levels do not influence neurocognitive performance.
authors: Queensland Centre for Mental Health Research, The Park Centre for Mental Health, Wacol, Australia. john_mcgrath@qcmhr.uq.edu.au
authors: John
authors: J
authors: McGrath
authors: Robert
authors: R
authors: Scragg
authors: David
authors: D
authors: Chant
authors: Darryl
authors: D
authors: Eyles
authors: Thomas
authors: T
authors: Burne
authors: Darja
authors: D
authors: Obradovic
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D002112:Calcifediol / Q000097:blood*; D003071:Cognition / Q000502:physiology*; D005260:Female; D006801:Humans; D007858:Learning / Q000502:physiology*; D008297:Male; D008875:Middle Aged; D009483:Neuropsychological Tests; D009749:Nutrition Surveys; D011594:Psychometrics
chemical_list: D002112:Calcifediol