Middle-aged and older women who naturally go to bed and get up early (early birds) are considerably less likely to be depressed, according to an observational study from the University of Colorado, Boulder, and Brigham and Women's Hospital in Boston. The researchers used data on 32,470 women involved in the Nurses’ Health Study II.
While prior studies have suggested that depression is twice as common in people who stay up late at night (night owls), most of that research didn’t account for other depression risk factors or determine cause and effect – that is, do people who are depressed tend to stay up late, or does staying up late boost depression risk?
For this study, participants – none of whom had depression – were asked about their sleep habits, and researchers assessed depression risk factors like body weight, activity levels, and chronic health problems. Overall, 37 percent of the study participants identified as early birds, 53 percent as intermediate, and 10 percent as night owls. Four years later, women who reported typically going to bed and waking up early were 12 to 27 percent less likely than intermediate types to be depressed, even after adjusting for other factors.
Sourced from: Journal of Psychiatric Research