Knowledge of vitamin D, Attitudes towards vitamin D and sun exposure and Prevalence of vitamin D supplement use in elite athletes.

Abstract

Background: Vitamin D deficiency is prevalent amongst athletes which could affect health, training and performance. Sun safety messages often dominate over vitamin D education and this is evident when investigating attitudes towards and knowledge of vitamin D and sun exposure in the general population. Knowledge of and attitudes towards vitamin D amongst athletes has not previously been researched. Such information is important when designing educational interventions and preventing or treating deficiency. Despite high rates of deficiency in elite athletes, few studies have documented the prevalence of vitamin D supplement use in this population. This study aimed to investigate: knowledge of vitamin D, attitudes towards sun exposure and vitamin D and the prevalence of vitamin D-containing supplement use in elite athletes. Design: 110 international-level New Zealand rugby (n=35), hockey (n=22) and rowing (n=55) athletes completed an interview-style questionnaire during summer months (February and March). The questionnaire consisted of 4 sections: Demographics, Knowledge of vitamin D, Supplements and Diet and Attitudes to sun exposure and vitamin D. Chi-squared testing was used to determine differences between gender, ethnicity and sport. Results: Almost all (97%) athletes had heard of vitamin D and two-thirds were able to name the sun as a source of vitamin D. Pacific Islanders were less likely to be able to name the sun as a source compared to Māori or New Zealand (NZ) Europeans (p=0.008). Only 17% of athletes were able to name another source of vitamin D, less than half (45%) of athletes were able to name a personal characteristic that affects vitamin D status and 29% could name one or more health benefits of having an adequate vitamin D status. Rowers tended to know the most about sources and health benefits of vitamin D. Only 5% of athletes were concerned about their vitamin D status but 12% intentionally spent time in the sun to improve their vitamin D. A larger proportion, one-third of athletes intentionally spent time in the sun with intention to tan, and two-thirds were concerned about the risk of skin cancer with sun exposure. Females and hockey players were more likely to spend time in the sun to tan and Pacific Islanders were the least likely to (p<0.05). Vitamin D, calcium and cod liver oil supplements were used by 6-7% of athletes and one-third used multivitamins. Conclusion: Elite athletes’ vitamin D knowledge was limited beyond knowing the sun is a source of vitamin D. The small proportion of athletes concerned about their vitamin D status understood more about vitamin D than those unconcerned, therefore educational interventions are likely to be successful. Vitamin D intake from food and supplements was not likely to be adequate to maintain summer status for most athletes. Concern of skin cancer predominated over concern of vitamin D status. Elite athletes require vitamin D education in order to improve knowledge of vitamin D and concern of their own status. This should be coordinated with sun safety messages to reduce risk of skin cancer whilst preventing vitamin D deficiency in athletes.