Testosterone is the primary hormone in men that fuels both sex drive and muscle growth. Regardless of a man’s age, testosterone is essential for optimal health. Along with controlling a man’s libido, testosterone works to build muscle, regulate emotions, maintain energy levels, and control fat distribution.
Testosterone decreases naturally as you age. Most men lose 1% of their testosterone each year, meaning there is a gradual decline over time. However, various environmental factors can affect testosterone levels and stop hormone production at an earlier time.
Injury, illness, stress, medications, obesity, alcoholism, and other environmental factors can all decrease testosterone levels. By the time a man is 55, he like has only 75% of the testosterone his body needs — of even less depending on his lifestyle.