A new study published in the journal Nature on May 13 indicates that sleep duration may directly influence the speed at which organs age. Scientists analyzed data from nearly half a million people in the UK and used advanced "biological aging clocks," based on machine learning, to measure wear and tear in 17 organ systems—including the brain, heart, lungs, liver, and immune system.
The study's lead author, Junhao Wen, assistant professor of radiology at the Vagelos College of Physicians and Surgeons at Columbia University in New York, explained that the team built aging clocks specific to each organ. "For the liver, for example, we have an aging clock built with protein data, another with metabolic data, and a third with imaging data," Wen said. "This allows us to see if sleep is distinctly associated with aging clocks derived from multiple molecular layers."
The results revealed a U-shaped pattern: people who slept less than 6 hours or more than 8 hours per night showed signs of faster biological aging throughout the body. The healthiest patterns were observed in those who slept between 6.4 and 7.8 hours per night.
Short sleep was associated with a higher risk of depression, anxiety, obesity, type 2 diabetes, hypertension, and heart disease. Both short and long sleep were linked to lung problems—such as chronic obstructive pulmonary disease (COPD) and asthma—and digestive disorders, including gastritis and acid reflux.
The researchers highlighted that the findings show how sleep is deeply connected to overall body function, not just brain health. Wen stated that the results support the idea that sleep plays a crucial role in maintaining organ health, including metabolic balance and a healthy immune system. Future studies should investigate whether improving sleep habits can help slow biological aging in different organs.