Optimal Sleep Window Linked to Slower Biological Aging Across Organs
A large study of about 500,000 UK Biobank participants using organ-specific aging clocks and machine-learning analysis found a U-shaped association between sleep duration and biological aging: both short (<6 hours) and long (>8 hours) sleep correlated with faster aging across organs such as the brain, heart, lungs, and immune system, while 6.4–7.8 hours per night was associated with healthier aging patterns. The work links sleep patterns to mental health and a range of diseases but does not establish causality; it suggests sleep duration is a modifiable factor in a coordinated brain–body aging process.