Bones, Joints, and TRT: How Testosterone Promotes Bone and Joint Health
Studies have shown that one of the most consistent effects testosterone therapy has on individuals is an increase in bone mineral density (BMD). As you get older, the risk of osteoporosis increases, which can result in painful fractures. Low BMD can cause bones to become brittle and more susceptible to injury.Your body stores 99% of its calcium in your bones and teeth, where it supports their structure and hardness. The remaining 1% circulates around your body, helping with nerve transmission and muscle contraction. Calcium levels are controlled by two hormones: parathyroid hormone (PTH) and calcitonin.As men age into their 60s or beyond, the chances of developing osteoporosis increase significantly due to declining testosterone production by their testes. A direct inverse correlation between testosterone levels and PTH has been found in many studies of older men with below-average T levels—the higher the PTH level was, the lower the testosterone level was found to be—and vice versa: When supplemental T therapy raised serum T levels in these studies’ subjects, PTH fell correspondingly. In other words, higher serum T levels reduce PTH secretion; conversely, low testosterone production raises PTH secretion as a compensating mechanism for preserving blood calcium homeostasis.
