We know that sleep is important for a host of body functions, from weight control to brain activities, but the latest study hints that it may also keep aging processes in check.

Scientists at the Duke-NUS Graduate School Singapore report in the journal Sleep that among a group of 66 elderly Chinese volunteers, those who reported sleeping less each night on average showed swelling of a brain region indicating faster cognitive decline.

The participants had MRI brain scans every two years, and answered questions about their sleep habits as well. Other studies have suggested that adults need about seven hours of sleep a night to maintain proper brain function; future research will investigate how sleep helps to preserve cognitive functions and hold off more rapid aging.

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