Summary: A comprehensive analysis of biological aging clocks across the human body shows that both too little and too much sleep are linked with accelerated aging in nearly every organ system.
This study identifies a coordinated U-shaped relationship between daily sleep duration and biological age. The results indicate that sleep is not only a brain-centered process but a vital factor in maintaining an integrated brain–body network that supports metabolic balance, immune function, and organ health across 17 organ systems.
Key Research Findings
- U-shaped association: Both short sleep (under 6 hours) and long sleep (over 8 hours) are associated with faster biological aging. The lowest biological aging was observed in people reporting between 6.4 and 7.8 hours of sleep per night.
- Organ-specific aging clocks: Using machine learning and UK Biobank data, researchers developed 23 aging clocks for 17 organs based on medical imaging, plasma proteins, and molecular measures. These clocks show that different organs age at different rates and respond uniquely to sleep patterns.
- Brain–body network: Short sleep showed strong links to mental health conditions (depression, anxiety) and systemic physical diseases including obesity, type 2 diabetes, hypertension, and cardiac arrhythmias.
- Respiratory and digestive effects: Both short and long sleep durations were associated with chronic obstructive pulmonary disease (COPD), asthma, and digestive issues such as gastritis and gastroesophageal reflux disease (GERD).
- Distinct pathways for late-life depression: Mediation analyses suggest short sleep may directly increase late-life depression burden, whereas long sleep may influence late-life depression through brain and adipose (fat tissue) aging clocks.
Source: Columbia University
Overview
The research, published in Nature, examined how self-reported sleep duration relates to biological ageing using a wide array of data types. Aging clocks—machine learning models that estimate biological age from molecular, proteomic, and imaging data—were trained for specific organs. These organ-specific clocks offer a more detailed view of physiological aging than whole-body measures alone and make it possible to study how lifestyle factors like sleep relate to each organ’s aging pattern.
How the study was done
Researchers analyzed data from roughly half a million participants in the UK Biobank. They built aging clocks using structural imaging, plasma proteomics, and metabolomic signatures for multiple organs. For example, liver aging was assessed with clocks built from protein markers, metabolic profiles, and imaging features. These multi-omics clocks allowed the team to test whether sleep duration was associated with consistent aging signals across biological layers and organ systems.
Main pattern and interpretation
Across the study population (ages ~37–84), a consistent U-shaped relationship emerged: sleeping less than ~6 hours or more than ~8 hours was associated with larger biological age gaps—meaning organs appeared older than chronological age—while the minimum gap occurred between 6.4 and 7.8 hours. The findings do not prove causation; instead, both short and long sleep may be markers of underlying health problems that affect organ aging.
Sleep and disease across the body
Beyond brain effects, sleep duration correlated with a range of systemic diseases. Short sleep showed strong associations with depressive episodes, anxiety disorders, obesity, type 2 diabetes, hypertension, ischemic heart disease, and arrhythmias. Both short and long sleep were linked with respiratory diseases (COPD, asthma) and gastrointestinal conditions (gastritis, GERD). These patterns support the idea that sleep duration is deeply integrated into whole-body physiology with implications for metabolic and immune health.
Late-life depression: different biological routes
Using mediation analysis, investigators explored whether aging clocks explain the links between sleep extremes and late-life depression. Results indicate short sleep may have a more direct association with depression burden, while long sleep appears to affect late-life depression partly through changes reflected in brain and adipose tissue clocks. This suggests different biological mechanisms may underlie similar clinical outcomes and highlights the potential for tailored prevention and treatment strategies.
Key Questions Answered:
A: This study used self-reported daily sleep duration, emphasizing that consistent sleep within the 6.4–7.8 hour range is likely more supportive of organ health than irregular or episodically prolonged sleep. Occasional catch-up sleep may not offset the effects of chronic insufficient or excessive sleep.
A: Long sleep may reflect or signal poorer overall health rather than directly causing organ aging. The study found long sleep associated with different biological pathways—such as adipose tissue aging—that can influence inflammation and systemic disease risk.
A: Aging clocks use machine learning models trained on molecular and imaging data—such as plasma proteins, metabolites, and organ structure—to estimate a biological age. Comparing that estimate to a person’s chronological age shows whether an organ appears biologically younger or older than expected.
Editorial Notes:
- Edited by a Neuroscience News editor.
- Journal article reviewed in full.
- Additional context provided by staff.
About this research
Author: Helen Garey
Source: Columbia University
Contact: Helen Garey – Columbia University
Image credit: Neuroscience News
Original Research (open access): “Sleep chart of biological aging clocks in middle and late life” by The MULTI Consortium et al., published in Nature. DOI: 10.1038/s41586-026-10524-5
Abstract (summary)
Optimal sleep plays a central role in healthy aging and longevity. The study proposes a Sleep Chart to quantify the relationship between self-reported sleep duration and 23 biological aging clocks derived from in vivo imaging, plasma proteomics, and metabolomics. A systemic U-shaped pattern appears across brain and body systems and multiple omics technologies, with the lowest biological age gaps observed between 6.4 and 7.8 hours of sleep. Short (<6 h) and long (>8 h) sleep durations, compared with 6–8 h, are associated with increased risk of systemic diseases and all-cause mortality, including depression and diabetes. The biological pathways linking sleep extremes to late-life depression differ: long sleep may act partially through aging clocks, while short sleep shows a more direct link. These findings highlight a cross-organ, multi-omics U-shaped relationship between sleep duration and biological aging and suggest that optimizing sleep may help promote healthy aging and reduce disease risk.