Fig.2
Sleepers awake
There’s more to a good night’s rest than going to bed early. Sleeping comes easiest and lasts longest for the wealthy, white, and female. Reporting her findings in the June 1 American Journal of Epidemiology, health-studies associate professor Diane Lauderdale, AM‘78, AM’81, followed the sleep habits of 669 Americans aged 35 to 50 and found that those with a yearly income of less than $16,000 spend longer in bed than those making $100,000 or more, but they sleep less because their “sleep latency,” the amount of time spent lying in bed awake, stretches to nearly an hour.
Using both self-kept sleep logs and wrist-activity monitors, Lauderdale also discovered that people sleep less than they realize: although participants reported averaging nearly seven hours per night, measured sleep was only about six.