India, May 15 -- An analysis of biological clocks throughout the human body suggests that too few hours of sleep-and too many-may speed ageing in the brain, heart, lung, and immune system and is associated with a wide range of diseases.

"Previous studies have found that sleep is largely linked to ageing and the pathological burden of the brain. Our study goes further and shows that too little and too much sleep are associated with faster ageing in nearly every organ, supporting the idea that sleep is important in maintaining organ health within a coordinated brain-body network, including metabolic balance, and a healthy immune system," says study leader Junhao Wen, assistant professor of radiology at Columbia University Vagelos College o...