Researchers Suggest a Sleep Target to Slow Aging

Turns out there really is a "just right" amount of shut-eye, and it's narrower than you might think. A massive UK Biobank analysis of about 500,000 people, published in Nature, found that regularly sleeping between roughly 6.4 and 7.8 hours a night was linked to slower aging in almost every major organ, from the brain to the heart, based on molecular "aging clocks" the researchers developed, per the Washington Post. Deviating in either direction from this so-called sweet spot formed a U-shaped curve: Both shorter and longer sleep were tied to biological signs of faster aging. Women appeared to benefit from slightly more sleep than men, by about 15 to 20 minutes in some brain measures.

Experts stress that the research shows correlation, not definitive proof that sleep duration causes aging changes, and they note that sleeping longer could also reflect underlying health problems or depression. Still, they say the takeaway is solid: Most adults seem to do best with consistent sleep in the six-to-eight-hour range, adjusted to how rested they feel during the day. Good sleep habits—morning light exposure, fewer late-night screens, and a dark, quiet, cool bedroom—remain the go-to prescription. These doctors have some other suggestions.