Poor or insufficient sleep reduces testosterone in young men

Few hours of sleep reduce testosterone levels in young men. Hormone deficiency causes fatigue, lack of concentration, loss of libido, and predisposition to obesity.

A study published in the Journal of the American Medical Association (JAMA) shows that young men who sleep less than five hours a day have their testosterone levels drastically reduced to the same amount as a 10 to 15-year-old adolescent.

To reach this conclusion, researchers randomly recruited ten young men in the vicinity of the University of Chicago, United States, with an average age of 24, lean and in good health. They underwent a rigorous battery of tests to detect possible endocrine or psychiatric disorders and sleep problems.

The participants also spent three nights in the laboratory sleeping for ten hours, and then eight more nights sleeping less than five hours. Blood samples were collected - every 15 to 30 minutes for 24 hours - during the last day of the ten-hour sleep phase and on the last day of the five-hour sleep phase.

The effects of insufficient sleep were apparent in testosterone levels after one week of short sleep duration. Five hours of sleep decreased hormone levels by 10% to 15%. The lowest testosterone levels were present during afternoons on days of restricted sleep, between 2 PM and 10 PM. Young men also reported drops in well-being that coincided with low blood testosterone levels, in addition to decreased mood and vigor each day their sleep was restricted.

Testosterone deficiency is associated with lack of energy, reduced libido, lack of concentration, fatigue, as well as bone density and muscle mass. According to the study, 15% of the economically active population of the United States sleeps less than five hours a day and, therefore, suffers various health effects.

Read more about hormone therapy in the Preventive Medicine section of our treatments.

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