The last decade has seen a dramatic increase in general interest in and research into vitamin D, with many athletes now taking vitamin D supplements as part of their everyday dietary regimen. The most recognized role of vitamin D is its regulation of calcium homeostasis; there is a strong relationship between vitamin D and bone health in non-athletic individuals. In contrast, data have consistently failed to demonstrate any relationship between serum 25[OH]D and bone health, which may in part be due to the osteogenic stimulus of exercise. Vitamin D may interact with extra-skeletal tissues such as muscle and the immune system to modulate recovery from damaging exercise and infection risk. Given that many athletes now engage in supplementation, often consuming extreme doses of vitamin D, it is important to assess whether excessive vitamin D can be detrimental to health. It has been argued that toxic effects only occur when serum 25[OH]D concentrations are greater than 180 nmol·l−1, but data from our laboratory have suggested high-dose supplementation could be problematic. Finally, there is a paradoxical relationship between serum 25[OH]D concentration, ethnicity, and markers of bone health: Black athletes often present with low serum 25[OH]D without physiological consequences. One explanation for this could be genetic differences in vitamin D binding protein due to ethnicity, resulting in greater concentrations of bioavailable (or free) vitamin D in some ethnic groups. In the absence of any pathology, screening may be unnecessary and could result in incorrect supplementation. Data must now be re-examined, taking into consideration bioavailable or “free” vitamin D in ethnically diverse groups to enable new thresholds and target concentrations to be established; perhaps, for now, it is time to “set vitamin D free”.
McCollum EV, Simmonds N, Becker JE, et al. Studies on experimental rickets. XXI. An experimental demonstration of the existence of a vitamin which promotes calcium deposition. J Biol Chem. 1922;53:293–312.
Academies The National, Reference Dietary. Dietary Reference intakes for calcium and vitamin D, vol. 1. Washington, DC: Institute of Medicine, National Academic Press; 2011.
Zehnder D, Bland R, Williams MC, et al. Extrarenal expression of 25-hydroxyvitamin d(3)-1 alpha-hydroxylase. J Clin Endocrinol Metab. 2001;86:888–94. PubMed
Bescos-Garcia R, Rodriguez-Guisado FA. Low levels of vitamin D in professional basketball players after wintertime: relationship with dietary intake of vitamin D and calcium. Nutr Hosp. 2011;26:945–51. PubMed
Pritchett K, Pritchett R, Ogan D, et al. 25(OH)D status of elite athletes with spinal cord injury relative to lifestyle factors. Nutrients. 2016;8:6. CrossRef
Valtuena J, Dominguez D, Til L, et al. High prevalence of vitamin D insufficiency among elite Spanish athletes the importance of outdoor training adaptation. Nutr Hosp. 2014;30:124–31. PubMed
Chen T, Chimeh F, Lu Z, et al. Factors that influence the cutaneous synthesis and dietary sources of vitamin D. Arch Bochem Biophys. 2007;460:213–7. CrossRef
Owens DJ, Sharples AP, Polydorou I, et al. A systems based investigation into vitamin D and skeletal muscle repair, regeneration and hypertrophy. Am J Physiol. 2015;309:E1019–31.
Barker T, Schneider ED, Dixon BM, et al. Supplemental vitamin D enhances the recovery in peak isometric force shortly after intense exercise. Nutr Metab. 2013;10:69. CrossRef
Agergaard J, Trostrup J, Uth J, et al. Does vitamin-D intake during resistance training improve the skeletal muscle hypertrophic and strength response in young and elderly men? A randomized controlled trial. Nutr Metab. 2015;12:32. CrossRef
Domingues-Faria C, Chanet A, Salles J, et al. Vitamin D deficiency down-regulates Notch pathway contributing to skeletal muscle atrophy in old Wistar rats. Nutr Metab. 2014;11:47. CrossRef
Glass DJ. PI3 kinase regulation of skeletal muscle hypertrophy and atrophy. Curr Top Microbiol Immunol. 2010;346:267–78. PubMed
Stockton KA, Mengersen K, Paratz JD, et al. Effect of vitamin D supplementation on muscle strength: a systematic review and meta-analysis. Osteoporos Int. 2011;22:859–71. PubMed
He CS, Aw Yong XH, Walsh NP, et al. Is there an optimal vitamin D status for immunity in athletes and military personnel? Exerc Immunol Rev. 2016;22:42–64. PubMed
Cannell JJ, Hollis BW. Use of vitamin D in clinical practice. Altern Med Rev. 2008;13:6–20. PubMed
Hewison M. An update on vitamin D and human immunity. Clin Endocrinol. 2012;76:315–25. CrossRef
Laaksi I, Ruohola JP, Tuohimaa P, et al. An association of serum vitamin D concentrations <40 nmol/L with acute respiratory tract infection in young Finnish men. Am J Clin Nutr. 2007;86:714–7. PubMed
He CS, Handzlik M, Fraser WD, et al. Influence of vitamin D status on respiratory infection incidence and immune function during 4 months of winter training in endurance sport athletes. Exerc Immunol Rev. 2013;19:86–101. PubMed
Achinger SG, Ayus JC. The role of vitamin D in left ventricular hypertrophy and cardiac function. Kidney Int. 2005;95:S37–42. CrossRef
Pilz S, Tomaschitz A, Marz W, et al. Vitamin D, cardiovascular disease and mortality. Clin Endocrinol. 2011;75:575–84. CrossRef
Cashman KD, Hill TR, Cotter AA, et al. Low vitamin D status adversely affects bone health parameters in adolescents. Am J Clin Nutr. 2008;87:1039–44. PubMed
Weidauer L, Minett M, Negus C, et al. Odd-impact loading results in increased cortical area and moments of inertia in collegiate athletes. Eur J Appl Physiol. 2014;114:429–38. CrossRef
Allison RJ, Farooq A, Hamilton B, et al. No association between vitamin D deficiency and markers of bone health in athletes. Med Sci Sports Exerc. 2016;47:782–8. CrossRef
Bischoff-Ferrari HA, Giovannucci E, Willett WC, et al. Estimation of optimal serum concentrations of 25-hydroxyvitamin D for multiple health outcomes. Am J Clin Nutr. 2006;84:18–28. PubMed
Allison RJ, Farooq A, Cherif A, et al. Why don't serum vitamin D concentrations associate with BMD by DXA? A case of being 'bound' to the wrong assay? Implications for vitamin D screening. Br J Sports Med. 2017. https://doi.org/10.1136/bjsports-2016-097130
- Vitamin D and the Athlete: Current Perspectives and New Challenges
Daniel J. Owens
Graeme L. Close
- Springer International Publishing
Neu im Fachgebiet Orthopädie und Unfallchirurgie
e.Med Kampagnen-Visual, Mail Icon II