One more reason for getting a good night's sleep: sleeping an extra hour a night
may help control coronary artery calcification, a major risk factor for heart
The effect, reported in the Dec. 24 issue of The Journal of the American Medical
Association, was so strong that the researchers concluded that one extra hour of
sleep was the equivalent of lowering systolic blood pressure to a normal 120
"While this is an intriguing new finding, this one study does not by itself
establish a causal relationship,” said Diane Lauderdale, the senior author and
an associate professor of epidemiology at the University of Chicago. “It may be
that there is some other factor that influences how much people sleep and
independently influences calcification."
The scientists followed 495 healthy men and women, ages 35 to 47, for five
years, measuring their sleep patterns with electronic monitoring devices and
examining their arteries with CT scans.
Over all, the group averaged 6.1 hours of sleep a night. But after controlling
for age, blood pressure, cholesterol and other factors, those who averaged an
extra hour’s sleep every night reduced their risk of calcification by about