Sleep regularity matters more than sleep duration or quality, study shows.
The measure of a good night's sleep is usually based on two things -- the amount of time spent sleeping and the quality of that sleep. But now researchers say there is a third factor that matters even more than the other two when it comes to maintaining good sleep habits, and that is having a regular schedule. Going to sleep and waking up at the same time every day has a profound effect on one's health.
A study just published in the journal Scientific Reports has found that adults who stick to a regular bedtime tend to weigh less, have lower blood sugar, and reduced risk of heart disease, diabetes, and hypertension. A regular sleep schedule helps the body's circadian rhythm to stay on track, while improving digestion and appetite.The researchers used a new test called the Sleep Regularity Index to assess the sleeping habits of 2,000 adults with an average age of 69. From Reuters: "The index looks at sleep variation across a 24-hour day and compares one day to the next to understand regular sleep and wake times as well as midday naps."
They found that people with greater irregularity in their sleep patterns tend to go to sleep later at night, feel sleepy and sleep more during the day, and experience reduced light exposure. These people were also more prone to stress and depression.
Lead study author Jessica Lunsford-Avery of Duke University Medical Center in North Carolina said,
“Among the three types of sleep problems - duration, regularity and timing as a morning lark or night owl - sleep regularity was the most consistently and strongly associated with health. That underscores the importance of it.”
Of course, there are many people for whom this may be impossible, such as night-shift workers or those with late-night obligations. But the takeaway is that it's worth trying to implement as much regularity into your schedule as possible, when you do have the chance. For those who don't have mandatory reasons to stay up late, we should all be making more of an effort to get to bed at the same time every night. Skip the late afternoon coffee. Turn off Netflix. Get off your phone. Try this calculator to figure out your optimal bedtime.
As neuroscientist Matthew Walker wrote last year, "The shorter your sleep, the shorter your life." Surely that's reason enough to get to bed on time.