What percentage of athletes have been found to have inadequate levels of vitamin D?

Research in the field of sports nutrition has consistently indicated that a significant proportion of athletes may have inadequate levels of vitamin D. Among the data examined, findings show that up to 54% of athletes have been identified with insufficient vitamin D levels, which have been linked to potential negative effects on athletic performance, immune function, and bone health. Maintaining adequate vitamin D levels is crucial given its roles in muscle function and overall health. This understanding is vital for those involved in athletic training and nutrition, as it emphasizes the need for assessment and potential supplementation in athletes, particularly in populations or geographical areas with limited sunlight exposure.