Bone loss and osteoporosis can result from a variety of conditions, including Vitamin D deficiency and diabetes. High cortisol levels resulting from an overproduction of cortisol by the adrenal glands can also promote loss of bone, and even osteoporosis if the levels of cortisol remain high for a long period of time.
Two of the most common causes of high cortisol are chronic stress and depression. This explains why chronic depression, including depression related to thyroid disease, might induce bone loss. Chronic stress and depressive conditions are often associated with high cortisol levels.
Research has indeed demonstrated that osteoporosis and osteopenia are common in depression, even in people whose age ranges between 35 and 50. It is quite likely that adequate stress management and treatment of depression will help prevent bone loss at an age where a person becomes predisposed to developing osteopenia, which can lead to osteoporosis over time.