Untreated hyperthyroidism or overtreated hypothyroidism can increase your risk for osteoporosis. However, thyroid hormone treatment for hypothyroidism that keeps the thyroid levels in the normal range does not increase the risk of osteoporosis. Bones generally renew themselves in a process called bone turnover or resorption. Because hyperthyroidism increases the body's metabolism, bone turnover also is increased. This increase causes old bone tissue to dissolve before new tissue is fully formed, which does not give the body enough time to produce enough minerals for the new bones. The result: thin or weakened bones—osteoporosis.