According to the National Osteoporosis Foundation, half of women over 50 will break a bone due to osteoporosis. While adults can take osteoporosis prevention measures, it’s also important to focus on adolescence, the period of time in which half a person’s bone accrual takes place.
A study into osteoporosis risk factors assessed certain traits alongside bone mineral density in girls aged 11-19. Smoking, alcohol consumption, depressive symptoms and anxiety symptoms were all considered as potential factors in bone mineral density. Researchers found that girls who smoked heavily had lower bone mineral density in the lumbar spine and hip at the end of adolescence; depression was associated with lower density in the lumbar spine. Alcohol and anxiety were not correlated with reduced bone density. See more on this study at www.sciencedaily.com.
The other result – that depressive symptoms correspond to reduced bone density – requires a bit more digging. We know that depression has physiological effects, such as fatigue, nausea and psychosomatic pain. However, this study, along with some others, points to a possible connection between the psychological condition and the very development of the human skeleton.
There are a few ways in which depression may affect bone growth. One is that depressed individuals may have decreased appetite, meaning they don’t consume sufficient nutrients like calcium to foster proper bone development. Another possible factor is physical activity. The fatigue typical of depression may encourage a sedentary lifestyle; since physical activity is crucial to the development of strong, healthy bones, inactivity encourages low density.
Another more complex way in which depression may lead to bone weakness involves the body’s stress response. One stress hormone, cortisol, has been suspected of causing a disproportion between osteoclasts – cells that break down bone tissue – and osteoblasts – cells that deposit new bone tissues, with the former taking the lead. Depressed individuals may exhibit chronically higher levels of cortisol that lead to weaker bones, particularly in adolescence when bones are forming most quickly. See www.nejm.org for more on the potential links between depression and bone health.