men move into middle age, they spend less time in deep sleep.
This decline may be linked to the decrease in the body's production
of the human growth hormone (HGH) and may contribute to the aging
process, including wear-and-tear of the cardiovascular system
and the tendency toward middle-age spread: love handles, double
chins, and potbellies.
study led by Chicago professor of medicine Eve Van Cauter, published
in the August 16 issue of the Journal of the American Medical
Association, chronicled sleep patterns and HGH secretions in healthy
men, charting changes that begin in the late 20s and early 30s.
The documented drop in the growth hormone, researchers found,
leads to increased fat tissue and abdominal obesity, reduced muscle
mass and strength, and reduced exercise capacity. With the drop
in HGH also comes a decrease in sleep: by the time men reach age
45, they have nearly lost the ability to fall into deep sleep,
the stage when brain waves get slower and larger. After age 50,
the average man's total sleep declined by about 27 minutes per
decade of age. The research also showed that men who get less
sleep, regardless of age, secrete less HGH.
actually know that if we increase deep sleep, we can increase
growth hormone," says Van Cauter. "The appearance of a paunch
belly can be delayed by a decade or two."
Cauter is currently testing an experimental drug to see if it
will increase deep sleep, although researchers wonder if it will
be worth the risk of medicating healthy people to slow natural
only on healthy men, the experiment leaves questions about the
effects of decreased deep sleep in women. In fact, pre-menopausal
women do not appear to experience such a decline in deep sleep.
Still, Van Cauter stresses the significance of quality sleep for
everyone, female or male, old or young. "Having good sleep is
something that should be right up there with priorities for maintaining
good health." -