Study Links Six to Eight Hours of Sleep with Slower Biological Aging

Researchers utilized 23 aging clocks across 17 organ systems, including the brain, heart, lungs, and immune system. They discovered that both insufficient sleep (less than six hours) and excessive sleep (more than eight hours) were associated with faster biological aging. Although these findings do not establish a direct causal relationship between sleep duration and organ aging, they suggest a significant link between sleep patterns and overall health.

Junhao Wen, an assistant professor at Columbia University Vagelos College of Physicians and Surgeons who led the study, noted that previous research has primarily focused on sleep's impact on brain aging. This study expands the understanding to show that both inadequate and excessive sleep are related to faster aging in nearly all organs.

The study highlights the concept of aging clocks, which are biological tools that estimate whether individuals or their organs appear older or younger than their actual age. By employing machine learning and data from the UK Biobank, researchers were able to assess these clocks using a variety of biological measures. A notable U-shaped pattern emerged, revealing that both short and long sleepers had higher biological age gaps compared to those sleeping six to eight hours.

Additionally, the researchers identified several health risks associated with abnormal sleep duration. Short sleep was correlated with depressive episodes, anxiety disorders, obesity, type 2 diabetes, hypertension, and heart diseases. Both short and long sleep durations were linked to chronic respiratory conditions and digestive disorders.

The study also explored the relationship between sleep duration and late-life depression, suggesting that short and long sleep might involve different biological pathways leading to similar outcomes. Wen emphasized the importance of distinguishing between the two sleep patterns in future sleep management strategies.

Importantly, the findings do not serve as strict guidelines for optimal sleep duration. Individual sleep needs can vary, and the research cannot assert that merely adjusting sleep duration will slow aging. While the six-to-eight-hour range may not be ideal for everyone, the study represents a significant investigation into the connection between sleep and aging throughout the body.

Researchers note that sleep patterns can be modified, potentially offering a practical avenue for reducing age-related health risks. The study prompts further investigation into whether these aging clocks can identify lifestyle factors that might safeguard health over time.