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The Ideal Bedtime for Good Health
New research reveals the best time to go to bed

Here’s a bedtime story I think you’ll really like, one that vindicates my lifelong early-to-bed, early-to-rise ways, one I plan to make required reading for my night-owl wife so we can maybe spend more of our waking hours together.
New research reveals the ideal hour to go to bed — or, rather, to fall asleep.
Falling asleep between 10 and 11 p.m. seems to be ideal, based on a study of 88,000 U.K. adults published in the European Heart Journal: Digital Health. People who fall asleep before or after that hour were notably more likely to develop heart disease during the multiyear study:
- Before 10 p.m.: 24% more likely
- 11 p.m. to midnight: 12% more likely
- After midnight: 25% more likely
The findings relate to the simple fact that evolution has programmed us to be active during the day and sleep when it’s dark, a pattern that modern lighting and indoor jobs allow us to break at our peril.
“The body has a 24-hour internal clock, called circadian rhythm, that helps regulate physical and mental functioning,” explains study author David Plans, PhD, a psychology researcher at the U.K.’s University of Exeter. “The results suggest that early or late bedtimes may be more likely to disrupt the body clock, with adverse consequences for cardiovascular health.”
The study measured sleep and wake times with wrist-worn trackers on people ages 43 to 79 for one week. Over the next 5.7 years, 3,172 of the participants suffered a heart attack, stroke, or were diagnosed with some other serious cardiovascular disease. The findings don’t prove cause-and-effect, but the research accounted for many other possible causes, including age, health measures, and lifestyle factors, and even sleep duration.
Let there be daylight
The prospect of an optimal bedtime doesn’t surprise me. Our deeply ingrained circadian rhythm is set by darkness, which triggers the brain to produce the sleep-inducing chemical melatonin, and daylight, which suppresses melatonin production. Screens and other artificial light in the evening mess with that biological clock, as does a…