Can't Get 8 Hours of Sleep? Do This Instead

If you're among the one in three Americans who fail to get the seven to nine hours of sleep each night that experts have long touted as ideal, fear not. New research suggests "sleep regularity" may be more important than sleep duration—at least "the day-to-day consistency of sleep-wake timing can be a stronger predictor for some health outcomes than sleep duration," reads the study published in the journal Sleep. Those who slept eight hours on a consistent schedule were found to have the lowest mortality risk, study co-author Angus Burns, a research fellow at Harvard Medical School, tells the Wall Street Journal. But as the outlet notes, sleeping six hours on a consistent schedule was "associated with a lower risk of early death than sleeping eight hours with very irregular habits."

Those with high sleep regularity had a 20% to 48% reduced risk of premature death from any cause than those with the most irregular sleep. They also had a 16% to 39% reduced risk of death from cancer and a 22% to 57% reduced risk of death from cardiometabolic causes, according to the study. For those who fail to get seven to nine hours of sleep per night, perhaps due to "social or job requirements," this shows that "if you're able to make it consistent at least, you'll be doing something for your health," Burns tells the Journal. He notes even those with high sleep regularity had some variability in sleep and wake times and recommends keeping those times to the same one to two-hour period, say 9pm to 11pm.

Experts say more and more research links irregular sleep to poor outcomes—for example, another recent study linked irregular sleep timing and duration with the thickening of plaque in arteries, per CNN—yet public guidance still focuses mainly on sleep duration. With that in mind, a panel of the National Sleep Foundation reviewed existing research and, in a report released in September, concluded daily regularity in sleep timing is important for health and performance. "The span of the negative outcomes that happened as irregularity went up was pretty striking," co-author Matthew Weaver, a Harvard Medical School instructor, told the Harvard Gazette, citing "more depression" and "lower general well-being," in addition to worse metabolic outcomes. (More sleep stories.)