Sleep Affects Testosterone Levels

The amount of sleep older men get can affect their testosterone levels, according to a University of Chicago study.

Researchers monitored the amount of nighttime sleep for 12 healthy men, ages 64 to 74, and then measured their morning testosterone levels.

The study found that the amount of sleep was an independent predictor of the men's total and free testosterone levels in the morning.

"The results of the study raise the possibility that older men who obtain less actual sleep during the night have lower blood testosterone levels in the morning," study author Dr. Plamen Penev said in a prepared statement.

"Although the findings suggest that how long a person sleeps may be an indicator of age-related changes in important hormone signals in the body, future studies are needed to determine the importance of these relationships for the health of older adults," Penev said.

The study was published in the April 1 issue of the journal Sleep.

Previous studies have linked lack of sleep with increased risk of serious health problems such as depression, obesity, diabetes and cardiovascular disease.