Consistent Bedtime Protects Brain Health as You Age

Full analysis

UCLA neuroscientist Gina Poe explains that every cell in the body runs on a circadian clock, and growth hormone — critical for tissue repair and memory consolidation — is released in a single large burst only during the first deep slow-wave sleep cycle of the night. If you go to bed significantly later than usual, you miss that burst entirely rather than simply delaying it, because your cells have already moved past the window when they're primed to respond. Poe specifically names consistent bedtimes as one of the best markers of good neurological health as people get older, making this a practical priority rather than just a general wellness tip.