Testosterone Levels

Testosterone is the male hormone that affects sexual features and development. The amount of testosterone in a man's body is controlled by the pituitary gland. If the level is low, then the pituitary gland releases luteinizing hormone (LH), which tells the testicles to make more testosterone. An issue with either the pituitary gland or the testicles can result in a low testosterone level. See Testosterone for more on this subject.

If a man has low levels of testosterone in his body, then his body might make a reduced number of sperm, resulting in a low sperm count. If a man's sperm count is too low, then he might have trouble conceiving a child. Determining whether a low testosterone level is causing the… [more]

Obesity, Illness Speed Testosterone Decline Testosterone levels in men decline with age. But are there other factors that influence this decline? That is what researchers from the New England Research Institutes wanted to find out. And they did identify other variables besides age involved with the hormone. To better understand how much of the decline in testosterone over time is due to aging and how much might be related to health and lifestyle changes, the researchers looked at data for 1,667 men 40 to 70 years old followed from 1987-1989 to 2002-2004. They were able to gather data for the entire time period on 35 percent, or 584, of the men. Sharper declines in testosterone occurred among men who developed a chronic illness… [more]