Six to Eight Hours of Sleep Linked to Slower Biological Aging

An observational study published in the journal Nature reveals that sleeping six to eight hours per night is associated with slower biological aging and a reduced risk of chronic diseases and premature mortality. An international research team, including experts from Columbia University, analyzed data from nearly 500,000 participants in the UK Biobank. Using 23 statistical tools known as biological clocks, they estimated the aging of various organs through MRI and blood tests. The findings indicate a U-shaped relationship, where both insufficient sleep (under six hours) and excessive sleep (over eight hours) correlate with accelerated aging in the brain, liver, immune system, pancreas, and adipose tissues. Additionally, disrupted sleep patterns were linked to higher risks of depression, type 2 diabetes, and cardiovascular disease. The study notes that optimal sleep duration may vary by organ and biological sex, with cardiac health favoring six hours and brain health favoring eight. Researchers emphasize that the relationship is likely bidirectional, suggesting sleep should be a key consideration in strategies to prevent unhealthy aging, though adjusting sleep alone may not guarantee disease prevention.