C H I C A G O, Aug. 16, 2000 -- Here’s some news that could keep middle-aged men
awake nights: A lack of quality sleep may contribute to love
handles and double chins.
Researchers at the University of Chicago found what appears tobe a link between middle-age spread and men’s sleep patterns asthey get older.
They found that the quality of men’s sleep decreases with agealong with the body’s production of growth hormone. The drop ingrowth hormone, in turn, is thought to lead to flab.
Looking for Answers
Now, the researchers are working to see if new types of sleepingpills or hormone injections can slow signs of aging.
“We actually know that if we increase deep sleep, we canincrease growth hormone,” said Eve Van Cauter, a professor ofmedicine who led the study, published in Wednesday’s Journal of theAmerican Medical Association.
The study of beauty sleep was limited to healthy men, and it isnot clear whether the findings apply to women.
Van Cauter and her team looked at sleep studies conducted on 149men from 1985 to 1999. They found that by the time men reach age45, they have nearly lost the ability to fall into deep sleep.
Men produce growth hormone primarily during that kind of sleep.In studies of the elderly, growth hormone deficiency has beenconnected to obesity and the loss of muscle mass.
Losing Deep Sleep
The men involved in the sleep studies were of normal weight andranged in age from 16 to 83. Researchers found that as the menmoved into mid-life, from ages 35 to 50, their total amount ofsleep remained fairly constant.
The amount of deep, or slow-wave, sleep, however, decreased fromnearly 20 percent of a normal night’s sleep for men 25 or youngerto less than 5 percent for those over 35. Growth hormone secretiondeclined by nearly 75 percent.
The study also found that after age 50, men’s total amount ofsleep declined by about 27 minutes a decade. They awoke morefrequently during the night and stayed awake longer.
REM sleep, associated with dreaming, also declined after age 50to about 50 percent of a young man’s level.
In an accompanying editorial, Dr. Marc R. Blackman of the JohnsHopkins University School of Medicine in Baltimore said researchersdo not know for certain whether sleep quality influences theproduction of hormones or if the change in hormone levels itself isresponsible for changes in sleep.
But Van Cauter said it is clear that more deep sleep producesmore growth hormone.
The research could be used to examine whether growth hormoneinjections could slow signs of aging in men during early mid-life,she said. Currently, such therapy is used mostly for men 65 orolder.