CNET: Tech website writer speaks with experts to find out how deadly sleep deprivation can be.

“There is no evidence that a lack of sleep can directly kill you,” deadpans Annie Miller, sleep specialist and psychotherapist at DC Metro Sleep and Psychotherapy.

One extremely rare, hereditary disease seems to cause death via sleep deprivation. Fatal familial insomnia (FFI) starts with mild insomnia but progresses quickly, eventually leading to a complete inability to sleep. FFI patients also exhibit symptoms of dementia, difficulty controlling the body and degeneration of autonomic functions, such as digestion and temperature regulation.

Still, this is a neurodegenerative disease that affects the brain, Miller says, and “it’s more likely that FFI patients die from neural degeneration, as opposed to lack of sleep.”

Interestingly, Miller encourages people not to be afraid of sleep deprivation, despite the known ill effects. “I think people are afraid of not sleeping and it contributes to the worsening of insomnia,” she says. “Think about parents of newborns. We are built to withstand a certain degree of sleep deprivation.” Miller has a good point. Humans seem to be relatively capable during periods of sleep deprivation, complete or partial, although daily tasks feel more difficult and mundane. Randy Gardner would certainly say so.

Get the full story at cnet.com.