title: Serum nutritional biomarkers and their associations with sleep among US adults in recent national surveys.
abstract: BACKGROUND
  The associations between nutritional biomarkers and measures of sleep quantity and quality remain unclear.
  
  
  METHODS
  Cross-sectional data from the National Health and Nutrition Examination Surveys (NHANES) 2005-2006 were used. We selected 2,459 adults aged 20-85, with complete data on key variables. Five sleep measures were constructed as primary outcomes: (A) Sleep duration; (B) Sleep disorder; (C) Three factors obtained from factor analysis of 15 items and labeled as "Poor sleep-related daytime dysfunction" (Factor 1), "Sleepiness" (Factor 2) and "Sleep disturbance" (Factor 3). Main exposures were serum concentrations of key nutrients, namely retinol, retinyl esters, carotenoids (α-carotene, β-carotene, β-cryptoxanthin, lutein+zeaxanthin, lycopene), folate, vitamin B-12, total homocysteine (tHcy), vitamin C, 25-hydroxyvitamin D (25(OH)D) and vitamin E. Main analyses consisted of multiple linear, logistic and multinomial logit models.
  
  
  RESULTS
  Among key findings, independent inverse associations were found between serum vitamin B-12 and sleep duration, 25(OH)D and sleepiness (as well as insomnia), and between folate and sleep disturbance. Serum total carotenoids concentration was linked to higher odds of short sleep duration (i.e. 5-6 h per night) compared to normal sleep duration (7-8 h per night).
  
  
  CONCLUSIONS
  A few of the selected serum nutritional biomarkers were associated with sleep quantity and quality. Longitudinal studies are needed to ascertain temporality and assess putative causal relationships.
authors.affiliation: National Institute on Aging, NIA/NIH/IRP, Baltimore, Maryland, United States of America.
authors.forename: May A
authors.initials: MA
authors.lastname: Beydoun
authors.affiliation: National Institute on Aging, NIA/NIH/IRP, Baltimore, Maryland, United States of America.
authors.forename: Alyssa A
authors.initials: AA
authors.lastname: Gamaldo
authors.affiliation: Pediatric Endocrinology, Diabetes and Metabolism Nemours Children's Clinic, Jacksonville, Florida, United States of America.
authors.forename: Jose A
authors.initials: JA
authors.lastname: Canas
authors.affiliation: Graduate program in Public Health, Eastern Virginia Medical School, Norfolk, Virginia, United States of America.
authors.forename: Hind A
authors.initials: HA
authors.lastname: Beydoun
authors.affiliation: National Institute on Aging, NIA/NIH/IRP, Baltimore, Maryland, United States of America; Department of Psychology, University of Maryland, Baltimore County, Baltimore, Maryland, United States of America.
authors.forename: Mauli T
authors.initials: MT
authors.lastname: Shah
authors.affiliation: National Institute on Aging, NIA/NIH/IRP, Baltimore, Maryland, United States of America; Department of Psychology, University of Maryland, Baltimore County, Baltimore, Maryland, United States of America.
authors.forename: Jessica M
authors.initials: JM
authors.lastname: McNeely
authors.affiliation: National Institute on Aging, NIA/NIH/IRP, Baltimore, Maryland, United States of America.
authors.forename: Alan B
authors.initials: AB
authors.lastname: Zonderman
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001205:Ascorbic Acid / Q000097:blood; D002338:Carotenoids / Q000097:blood; D020920:Dyssomnias / Q000097:blood* / Q000453:epidemiology / Q000503:physiopathology; D005260:Female; D005492:Folic Acid / Q000097:blood*; D006710:Homocysteine / Q000097:blood; D006801:Humans; D008297:Male; D008875:Middle Aged; D015233:Models, Statistical; D009749:Nutrition Surveys; D009752:Nutritional Status; D012890:Sleep / Q000502:physiology*; D014481:United States / Q000453:epidemiology; D014801:Vitamin A / Q000097:blood; D014805:Vitamin B 12 / Q000097:blood*; D014807:Vitamin D / Q000031:analogs & derivatives* / Q000097:blood; D014810:Vitamin E / Q000097:blood
chemical_list: D006710:Homocysteine; D014801:Vitamin A; D014807:Vitamin D; D014810:Vitamin E; D002338:Carotenoids; D005492:Folic Acid; C104450:25-hydroxyvitamin D; D014805:Vitamin B 12; D001205:Ascorbic Acid