Calcium and
vitamin D are recognized
as 2 components of nutrition needed to achieve and maintain bone health.
Calcium and
vitamin D have been clearly shown to improve bone density and prevent fractures at all ages. However, the literature is conflicting as to the role of these nutrients in young athletes ages 18 to 35 years, both for bone development and for the prevention of bone
overuse injuries. Differences in findings may relate to study design. Although retrospective and cross-sectional studies have had mixed results, the authors of prospective studies have consistently demonstrated a relationship of increased
calcium intake with an improvement in bone density and a decrease in fracture risk. A randomized trial in female military recruits demonstrated that
calcium/
vitamin D supplementation reduced the incidence of
stress fractures. A prospective study in young female runners demonstrated reduced incidence of
stress fractures and increased bone mineral density with increased
dietary calcium intake. Findings from both studies suggest female athletes and military recruits who consumed greater than 1500 mg of
calcium daily exhibited the largest reduction in
stress fracture injuries. To date, no prospective studies have been conducted in male athletes or in adolescent athletes. In most studies, males and nonwhite participants were poorly represented. Evidence regarding the relationship of
vitamin D intake with the prevention of fractures in athletes is also limited. More prospective studies are needed to evaluate the role of
calcium and
vitamin D intake in prevention of
stress fracture injuries in both male and female adolescent athletes, particularly those participating in sports with greater incidences of
stress fracture injury.