Less Sleep May Lower Testosterone
Poor Sleep Tied to Declining Testosterone Levels Among Older Men
April 2, 2007 -- Less sleep may be linked to lower testosterone among older
men, according to a new study.
Men’s testosterone levels typically decline with age, and in some men that
drop in male hormones can lead to a lack of energy or libido as well as an
increased risk of falls with broken bones.
But researchers say some men in their 80s manage to maintain testosterone
levels usually seen in young men. The reasons behind the large variation in
testosterone levels aren’t understood, and researchers say their findings
suggest sleep may play a role.
"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," says researcher Plamen Penev, MD, PhD of the University of
Chicago, in a news release.
Less Sleep, Lower Testosterone
In the study researchers measured morning testosterone levels in 12 healthy
men between ages 64 and 74. Their sleep was also monitored over the course of
about a week.
The results showed that the amount of sleep the men got was a significantly
related to the amount of testosterone in morning blood samples. The more sleep
the men got, the higher their testosterone level, and those with less sleep had
lower testosterone levels (the range of sleep was four hours to eight hours
with an average of six hours).
"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," says Penev.
Sleep experts recommend that adults get between seven and eight hours of
sleep per night to maintain optimum health.
The findings appear in the April issue of Sleep.