Women need more sleep than men, according to a recent study. Researchers from Duke University have discovered that, compared to men, women experience more mental and physical consequences from inadequate rest. Besides giving half the population a legitimate reason to sleep in, the findings could also inspire new health recommendations for women at greater risk of heart disease, depression, and psychological problems.

The study, which was led by clinical psychologist and sleep expert Michael Breus, estimated men and women’s respective needs for sleep by assessing their ability to deal with insufficient rest. According to Breus, the experiment suggested a sharp difference between genders. "We found that women had more depression, women had more anger, and women had more hostility early in the morning," he told reporters.

Who Needs How Much?

Many biological factors are thought to contribute to this disparity. However, some experts believe that it ultimately comes down to mental energy expenditure. Women, they say, simply use their brain more than men do.

"One of the major functions of sleep is to allow the brain to recover and repair itself. During deep sleep, the cortex — the part of the brain responsible for thought, memory, language and so on — disengages from the senses and goes into recovery mode,” Jim Horne, director of the Sleep Research Center at Loughborough University in England, told The Australian. "The more of your brain you use during the day, the more of it that needs to recover and, consequently, the more sleep you need. Women tend to multi-task — they do lots at once and are flexible — and so they use more of their actual brain than men do.”

It follows that, if men used their brains more during the day, they would need a couple of extra hours too. "A man who has a complex job that involves a lot of decision-making and lateral thinking may also need more sleep than the average male — though probably still not as much as a woman,” Horne said.

The Science of Sleep

Breus’ and his colleagues’ study adds to a growing number of scientific inquiries into the health outcomes of sleep deprivation. In a paper published earlier this year, researchers from Case Western Reserve University School of Medicine showed a correlation between inadequate rest and accelerated skin aging. Other studies have linked poor sleeping patterns to an elevated risk of heart disease, blood clots, stroke, and psychiatric problems.

The average American adult requires between 7 and 9 hours of sleep every day. That said, 80 percent of the population say they habitually fall short of this quota. To learn more about sleep and improving rest patterns, visit The National Sleep Foundation’s online resources.