Day light savings

Daylight Saving Time “fall back” doesn’t equal sleep gain

Anthony Komaroff, M.D.

Executive Editor, Harvard Health Letter

Daylight Saving Time officially ends at 2:00 am this Sunday. In theory, “falling back” means an extra hour of sleep this weekend. But it doesn’t usually work out that way. Many people don’t, or can’t, take advantage of this weekend’s extra hour of sleep. And the focus on gaining or losing an hour of sleep overlooks the bigger picture—the effect of Daylight Saving Time transitions on the sleep cycle. This seemingly small one-hour shift in the sleep cycle can affect sleep for up to a week. It’s difficult to side-step the effects of Daylight Saving time on sleep. So be aware that it can take your sleep rhythms a week or so to get adjusted to the new clock.