Prevalence of Vitamin D Insufficiency in Professional Hockey Players

BACKGROUND Vitamin D is a fat-soluble hormone that plays a role in bone health, muscle function, and athletic performance. Studies have shown that low levels of vitamin D can lead to slower muscle recovery and function, increased rates of stress fractures, and even poorer athletic performance. Insufficient vitamin D levels have been demonstrated in professional basketball and football players, however, there have been no studies to date reviewing vitamin D insufficiency in professional hockey players. PURPOSE/HYPOTHESIS The purpose of this study was to perform a cross-sectional review to determine the prevalence of vitamin D deficiency and insufficiency in professional hockey players. The hypothesis was that there would be a high percentage of players with vitamin D insufficiency. STUDY DESIGN Cross-sectional study; Level of evidence, 3. METHODS The preseason serum 25-hydroxy (OH) vitamin D laboratory test results of 105 professional hockey players were retrospectively reviewed. All players on 3 National Hockey League (NHL) teams were included. Player parameters evaluated included age, height, weight, body mass index, and 25(OH) vitamin D level. Players were divided into 4 groups based on serum vitamin D levels: deficient (<20 ng/mL), insufficient (20-31.9 ng/mL), sufficient (≥32 ng/mL), and ideal (≥40 ng/mL). Descriptive statistics were performed, in addition to 2-group and 3-group comparisons. RESULTS The average 25(OH) vitamin D level of 105 players was 45.8 ± 13.7 ng/mL (range, 24-108 ng/mL). No players in the study were considered deficient. A total of 14 players (13.3%) were considered insufficient, while 91 players (86.7%) were considered sufficient. However, only 68 players (64.8%) were considered ideal. When comparing groups, athletes with sufficient vitamin D levels were older than athletes with insufficient vitamin D levels (25.9 vs 23.1 years; P = .018). All other player parameters demonstrated no significant difference between groups. CONCLUSION Despite playing a winter sport and spending a great deal of time training indoors, professional hockey players have low levels of vitamin D insufficiency.