Today, Randy Gardner is alive and well at 68 years of age, in spite of staying awake for more than 264 hours straight back when he was just 17.

Not only did he set a record for sleep deprivation, Gardner showed you can miss out on shut-eye for more than a week and still not risk an early grave. But before brewing a pot of extra strong coffee, there are a few things you ought to know first.

Forget nightmare-inducing creepy-pasta memes about secret Russian experiments; there is zero evidence that you can die from a lack of sleep.

While longer episodes of sleep deprivation have been noted in individuals (up to 449 hours in one case), Gardner's 11-day marathon has remained notable for its level of scientific scrutiny.

On learning about the school science experiment, Stanford University psychiatrist William C. Dement took the rare opportunity to observe and record Gardner's brain waves throughout the ordeal.

As you might expect, things weren't all clear sailing for the subject.

After three days, Gardner was getting moody and losing coordination. Bit by bit his senses were being affected, including his smell.

By day five he was hallucinating, his brain slipping into a dream-like state.

Follow-up analyses of Gardner's brain activity found he wasn't quite as fully awake as it appeared, with various parts of the brain shutting down for a siesta from time to time.

While it wasn't a pleasant experience, there is nothing to suggest Gardner's long-term health was in danger.

Where this gets particularly interesting is the fact that those findings are in stark contrast with experiments that had earlier been conducted on sleep-deprived animals (ugh, we know).

In 1898 two Italian physiologists kept dogs awake by constantly walking them over a period of several weeks, until, tragically, they died from what appeared to be degradation of various nerves in the brain and spinal cord.

Similar experiments on rats have also shown that a lack of sleep can be deadly.

But for some reason, humans appear to have evolved neurological tricks similar to those of some birds and aquatic mammals – an ability to shut down parts of the brain for maintenance while sort-of staying awake.

Our ability to slip into microsleep when we push past our limits might have helped us stay alive in the past, possibly in line with other endurance-enhancing adaptations that let us stay on the move for long periods.

But in today's busy world, we might be taking too much of an advantage of our flexible sleeping routine. And it comes at a heavy cost.

Karyn O'Keefe from the Sleep/Wake Research Centre at Massey University in New Zealand told ScienceAlert lack of sleep dramatically raises the risk of injury or accident while carrying out safety-sensitive tasks.

"For example, lack of sleep has been shown to substantially increase our risk of having a motor vehicle accident," she explains.

O'Keefe cites a US study that indicated having between four and five hours of sleep made you four times more likely to have a motor accident, compared to those who got around eight hours of solid sleep.

"With respect to risk of work-related injury, a large US study has shown that workers who got less than 5 hours sleep per day were 2.7 times more likely to have a work-related injury than those who got 7 to 7.9 hours' sleep," says O'Keefe.

If you're fortunate enough to avoid an accident, a consistent lack of sleep plays havoc with other aspects of your health.

"In the long-term, lack of sleep has been shown to lead to problems with physical health, such as increased risk for obesity, type 2 diabetes, cardiovascular disease and stroke, as well as increased risk for depression and anxiety," says O'Keefe.

Given most of us aren't getting enough sleep, this is a significant problem that might only worsen in the future.

For some unfortunate individuals, lack of sleep doesn't come with an easy fix. And in rare cases, insomnia could itself be a sign of something far more insidious.

"Fatal familial insomnia is an extremely rare hereditary prion disease which attacks the brain," Sleep/Wake Research Centre clinical psychologist Lora Wu told ScienceAlert.

"Insomnia is often an early symptom of what is a rapidly neurodegenerative condition resulting in death, typically within two years."

Before you reach for Dr Google at 3 am in a panic over having a deadly prion disease, you should know fewer than 60 cases among 27 families have been reported worldwide. You're probably safe.

The take-home message is insomnia is quite unlikely to either kill you, or be a sign of anything to worry about.

But those late nights binging on Netflix could catch up to you, so best not take that risk.