Testosterone is the primary androgen — or male hormone — in your body. Low testosterone affects up to 39 percent of adult men in the US over the age of 45, and becomes increasingly prevalent as men ...

Men with below-normal testosterone levels had a 40 percent higher risk of death from any cause compared with men with levels in the high-normal range. Men with extremely low T were about 60 percent ...

Dear Dr. Roach: The results for my last bone density test show not only a T-score but also a Z-score. For my spine (L1 through L4), the T-score is -3.4, while the Z-score is -1.4. Can you please ...