title: Vitamin D profile in National Football League players.
abstract: BACKGROUND
  By maintaining phosphate and calcium homeostasis, vitamin D is critical for bone health and possibly physical performance. Hence, vitamin D is important to athletes. Few studies have investigated vitamin D levels in relation to fractures and performance in athletes, and no published study has included a multiracial sample of professional American football players.
  
  
  OBJECTIVE
  To assess vitamin D levels, including the prevalence of vitamin D deficiency/insufficiency, in professional American football players and to evaluate the association of vitamin D levels with race, fracture history, and the ability to obtain a contract position, which may be a marker for athletic performance.
  
  
  METHODS
  Cohort study; Level of evidence, 3.
  
  
  METHODS
  Serum vitamin D levels of 80 professional football players from a single team in the National Football League were obtained during the 2011 off-season (mean age, 26.5±3.7 years; black, n=67 [84%]). These levels were used to compare injury reports from the 2011-2012 and 2012-2013 seasons. Statistical analyses were performed to test if vitamin D levels were related to race, fracture history, and the ability to obtain a contract position.
  
  
  RESULTS
  Mean vitamin D level was 27.4±11.7 ng/mL, with significantly lower levels for black players (25.6±11.3 ng/mL) versus white players (37.4±8.6 ng/mL; F 1,78=13.00, P=.001). All athletes who were vitamin D deficient were black. When controlling for number of professional years played, vitamin D levels were significantly lower in players with at least 1 bone fracture when compared with no fractures. Players who were released during the preseason because of either injury or poor performance had significantly lower vitamin D levels than did players who played in the regular season.
  
  
  CONCLUSIONS
  Black professional football players have a higher rate of vitamin D deficiency than do white players. Furthermore, professional football players with higher vitamin D levels were more likely to obtain a contract position in the National Football League. Professional football players deficient in vitamin D levels may be at greater risk of bone fractures.
authors: Department of Neurosurgery, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania, USA.
authors: Joseph C
authors: JC
authors: Maroon
authors: Department of Neurosurgery, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania, USA.
authors: Christina M
authors: CM
authors: Mathyssek
authors: Department of Neurosurgery, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania, USA bostj@upmc.edu.
authors: Jeffrey W
authors: JW
authors: Bost
authors: Department of Neurosurgery, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania, USA.
authors: Austin
authors: A
authors: Amos
authors: Department of Neurosurgery, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania, USA.
authors: Robert
authors: R
authors: Winkelman
authors: University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA.
authors: Anthony P
authors: AP
authors: Yates
authors: University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA.
authors: Mark A
authors: MA
authors: Duca
authors: Pittsburgh Steelers Football Club, Pittsburgh, Pennsylvania, USA.
authors: John A
authors: JA
authors: Norwig
mesh_terms: D000328:Adult; D001741:Black or African American; D056352:Athletes; D054874:Athletic Performance / Q000502:physiology*; D015331:Cohort Studies; D005538:Football / Q000293:injuries / Q000502:physiology*; D006801:Humans; D008297:Male; D015995:Prevalence; D014807:Vitamin D / Q000097:blood*; D014808:Vitamin D Deficiency / Q000453:epidemiology*; D044465:White People; D055815:Young Adult
chemical_list: D014807:Vitamin D
keywords: 25-hydroxyvitamin D; athletic training; football; injury prevention; vitamin D