Bones are metabolically active tissues. Old bones are broken down and new bone tissues are formed. Adolescence is the most active period of this cycle and the peak bone mass (PBM) is reached. In this period, reaching the PBM is depend on adequate and balanced nutrition. Achieving this ideal level reduces the risk of bone fractures and protects them from diseases such as osteoporosis during the adulthood.
Physical activity is generally associated with good bone health. But in some cases and in some sports, athletes may be at risk of low bone mineral density (BMD).
Energy Requirement: There may be deficiencies in energy intake in sports branches that require aesthetic or weight control (ballet, gymnastics, rowing, swimming etc.). Inadequate energy intake in adolescent athletes prevents reaching the PBM. This is because without sufficient energy, the body prioritises other essential processes (e.g. circulation, breathing etc.) ahead of bone health. This condition affects the health of the athletes and increases the risk of bone injuries (stress fractures, etc.).
Calcium and Vitamin D: Calcium and Vitamin D play a key role in bone development. Calcium requirement increases due to growth in adolescence. This mineral is found in the structure of bones, teeth and a certain amount of carried in the blood. When dietary intake is reduced, calcium is excreted from the bones to the bloodstream and the BMD decreases. To protect bone health, the recommended intake of calcium for adolescents is 1300mg per day. Vitamin D increases the absorption of calcium and is an essential vitamin for it is metabolism. Vitamin D is available in the diet, but most individuals obtain the majority of their vitamin D from exposure to sunlight. Therefore, athletes who train indoor or wear clothing during the activity may have vitamin D deficiencies. As a result, deficiencies in calcium and vitamin D result in a decrease in BMD and thus the bone health and development is negatively affected.
Protein Requirement: Excess protein intake increases bone loss, however, there is no scientific evidence that in healthy athletic individuals that reported protein intakes negatively affect bone health.
Caffeine Consumption: Caffeine inhibits the absorption of calcium from the gut and increases urinary excretion. However, research shows that these effects are minimal in individuals who are consuming sufficient amount calcium in their daily diet.
Compiled by: Dietitian Dilara Serarslan, Beyzadeoğlu Clinic
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