The recommended amount of sleep per night is seven hours, but how long can you really go without any sleep at all? Well, 17-year-old Randy Gardner stayed awake for 11 days and 25 minutes for a high school science fair project in 1963 while Robert McDonald went an entire 18 days and 22 hours without sleeping in 1986. However, due to the "inherent dangers associated with sleep deprivation," the Guinness World Records no longer considers the option.
Sleep is necessary for everyday function, and a lack of sleep can lead to a number of health conditions, from heart disease to diabetes and depression. Although experts recommend seven hours on average every 24 hours, many people, specifically students, pull all-nighters and stay awake for way too long. After a full day without sleep, one's brain activity begins to show signals they are on the sleep-wake border, even though they are physically awake. Sleep intrusion, or microsleep, is people that appear awake, but after hours without sleep, their brain goes into an abnormal sleep cycle. This could eventually lead to hallucinations or stages of inattention. "I would be hard-pressed to believe that someone can stay awake for more than 24 hours without these episodes," Dr. Oren Cohen said.
However, it is difficult to determine exactly how long people can go without sleep, as experts find it unethical to research the topic with humans. Chronic sleep deprivation is a horrible condition, so much so it's even been used as a form of psychological torture.
In 2019, Nature and Science of Sleep reported a participant's alertness and vigilance were considered normal, up to 16 hours without sleep. Still, afterward, their lack of attention increased and was even more difficult for those with chronic insomnia. The effects from a separate study found after 24 hours, participants suffered from slurred speech, impaired decision-making, irritability, impaired vision, and much more. At 36 hours, individuals could start developing inflammatory markets in their blood which may lead to hormone imbalances and a slowed metabolism, according to Cleveland Clinic. So, the moral of this story is to get in those seven hours every night!