Sleep deprivation reduces testosterone levels in young men.

Just one week of sleep deprivation reduces young men’s testosterone levels by as much as 15 percent, according to a 2011 study. Missing out on sleep worsened the young men’s mood and overall energy levels, too.

In the study, 10 young, healthy, college-age men got a good night’s sleep for three nights, and then they got just five hours per night for eight nights. Researchers monitored their sleep and collected blood samples from the men every 15 to 30 minutes throughout the last day of each sleep protocol.

They found that getting five hours of sleep a night for just one week drastically reduced the men’s testosterone levels – by as much as 10 to 15 percent. Testosterone levels began to plummet in the afternoons and continued to drop until late at night. The men also experienced marked reductions in their overall energy levels and moods.

Roughly one-third of working adults in the United States get fewer than six hours of sleep every night – a problem linked with a variety of acute and chronic health conditions, including an increased risk of colds, high blood pressure, diabetes, heart attack, heart failure, and stroke. Evidence suggests that poor sleep reduces sex drive.

The findings from this study suggest that getting even a few nights of poor sleep alters testosterone, energy levels, and mood in young, healthy men. Learn about other effects of sleep deprivation in this clip featuring Dr. Matthew Walker.

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