The recommended eight hours’ shut-eye may not be enough, say researchers, as most people sleep for 90% of their time in bed. So what effect do different amounts of sleep time really have on the body?
Penn State University researchers claim we need eight and a half hours for sleep. Their reason? Most people only sleep 90% of their time in bed, so you need that extra half hour if you want to have eight hours real sleep.
Good sleep is worth the effort – but how long do you need?