Vitamin D status relative to diet, lifestyle, injury, and illness in college athletes.
Vitamin D deficiency is endemic in the general population; however, there is much to be learned about the vitamin D status of athletes.


OBJECTIVE
the purposes of this study were to assess the prevalence of vitamin D insufficiency in collegiate athletes and to determine whether 25(OH)D concentrations are related to vitamin D intake, sun exposure, body composition, and risk for illness or athletic injury.


METHODS
25(OH) vitamin D concentrations were measured in 41 athletes (18 men/23 women, 12 indoor/29 outdoor athletes) throughout the academic year. Dietary intake and lifestyle habits were assessed via questionnaire, bone density was measured by dual energy x-ray absorptiometry, and injury and illness were documented as part of routine care.


RESULTS
the 25(OH)D concentrations changed across time (P = 0.001) and averaged 49.0 ± 16.6, 30.5 ± 9.4, and 41.9 ± 14.6 ng·mL (mean ± SD) in the fall, winter, and spring, respectively, and were higher in outdoor versus indoor athletes in the fall (P < 0.05). Using 40 ng·mL as the cutoff for optimal status, 75.6%, 15.2%, and 36.0% of athletes had optimal status in the fall, winter, and spring, respectively. 25(OH)D concentrations were significantly (P < 0.05) correlated with multivitamin intake in the winter (r = 0.39) and tanning bed use in the spring (r = 0.48); however, status was otherwise not related to intake, lifestyle factors, or body composition. 25(OH)D concentrations in the spring (r = -0.40, P = 0.048) was correlated with frequency of illness.


CONCLUSIONS
our results suggest that collegiate athletes can maintain sufficient status during the fall and spring but would benefit from supplementation during the winter to prevent seasonal decreases in 25(OH)D concentrations. Results further suggest that insufficient vitamin D status may increase risk for frequent illness. Future research is needed to identify whether vitamin D status influences injury risk during athletic training or competition.
Halliday
Tanya M
TM
Department of Family and Consumer Sciences, University of Wyoming, Laramie, WY 82071, USA.
Peterson
Nikki J
NJ
Thomas
Joi J
JJ
Kleppinger
Kent
K
Hollis
Bruce W
BW
Larson-Meyer
D Enette
DE
D015502:Absorptiometry, Photon; D000293:Adolescent; D056352:Athletes; D001265:Athletic Injuries / Q000453:epidemiology* / Q000209:etiology / Q000517:prevention & control; D015519:Bone Density; D004032:Diet; D005260:Female; D006801:Humans; D008019:Life Style; D008137:Longitudinal Studies; D008297:Male; D010281:Parathyroid Hormone / Q000097:blood; D015995:Prevalence; D014807:Vitamin D / Q000008:administration & dosage* / Q000097:blood*; D014808:Vitamin D Deficiency / Q000150:complications / Q000453:epidemiology* / Q000517:prevention & control; D055815:Young Adult
D010281:Parathyroid Hormone; D014807:Vitamin D