Testosterone is the quintessential male hormone (androgen), and it’s a busy one, helping to regulate intimate function, muscle mass, red blood cell count, mood, and more. But not all testosterone in ...

Reviewed by Clifton Jackness, MD, attending physician in Endocrinology, Diabetes, and Metabolism at Lenox Hill Hospital and The Mount Sinai Medical Center in New York City Age-related decline of ...

Sun, January 11, 2026 at 1:56 PM UTC If you’ve ever had your testosterone levels checked, you may have come across two different numbers: one for free testosterone and the other for total testosterone ...

Testosterone levels are at their highest during adolescence and early adulthood. Testosterone levels may start to decline after age 30 years in males and between ages 45 and 55 years in females.

When it comes to understanding testosterone levels, traditional testing reports one number: total testosterone. But there's more to the story, especially for men who may be experiencing symptoms of ...