How long can you go without sleep? Although it’s unclear exactly how long humans can survive without sleep, the longer time registered has been 11 days. But the effects of sleep deprivation start to show much sooner. In this article, we explore the key facts behind sleeping and the consequences of not getting enough of it
The Center for Disease Control and Prevention (CDC) recommends that adults between the ages of 18 and 60 years get at least 7 hours of sleep a night. The number of hours varies according to your age. In general, newborns and infants need more sleep, and adults need less sleep.
However, approximately 35 percent of adults in the United States do not get enough sleep. Adults should stay awake no longer than 17 hours to meet the CDC’s sleep recommendation. People tend to experience the adverse effects of sleep deprivation within 24 hours.
Randy Gardner beat the record for staying awake the most in 1964, making it into the Guinness Book of Records. Gardner, then 17, was up for 11 days and 25 minutes. Though he did not experience physical symptoms right after his endeavor, he reportedly suffered from insomnia for years.
Gardner’s 264 hours remains the longest scientifically verified period without sleep, breaking the previous record of 260 hours. It was described in a 1965 paper by sleep researcher William Dement of the Stanford University School of Medicine in California, who stayed awake with Gardner for the final three days.
According to Dement, Gardner did not consume any stimulants during his “wakeathon”. He did, however, have people around him keeping him awake. Without such help, you would be fighting hard to stay awake after 36 hours and would find the urge to sleep.
Missing a day of sleep can be quite common because of work, studying or taking care of your kids, among many reasons. While it might be unpleasant to stay up all night, it won’t have a significant impact on your overall health.
Nevertheless, missing a night of sleep does affect you. Studies have compared 24-hour wakefulness to having a blood alcohol concentration of 0.10 percent. This is above the legal limit to drive in most states.
Some effects of going 24 hours without sleep include: drowsiness, irritability, impaired decision-making, impaired judgment, altered perception, memory deficits, vision and hearing impairments, decreased hand-eye coordination and increased muscle tension. Symptoms of 24-hour sleep deprivation usually go away once you sleep.
After two nights of missed sleep, most people have difficulty staying awake. They might experience periods of light sleep that can last up to 30 seconds. During these “microsleeps,” the brain is in a sleeplike state. Microsleeps happen involuntarily. After a microsleep, you might feel confused or disoriented.
Staying awake for 48 hours also disrupts the immune system. Inflammatory markers, which help your body prevent and target illnesses, start to circulate at increased levels. Some research has shown that natural killer (NK) cell activity decreases with sleep deprivation. NK cells respond to immediate threats to your health, such as viruses or bacteria.
Staying awake for just 36 hours can have intense effects on your body. Your sleep-wake cycle helps regulate the release of certain hormones, including cortisol, insulin, and human growth hormone.
As a result, going without sleep for an extended period of time can alter several bodily functions. This includes your: appetite, metabolism, temperature, mood and stress level, among other functions.
Some effects of going 36 hours without sleep include: extreme fatigue, hormonal imbalances, decreased motivation, risky decisions, inflexible reasoning, decreased attention and speech impairments, such as poor word choice and intonation
After 72 hours without sleep, most people experience an overwhelming urge to sleep. Many are unable to stay awake on their own.
Going three days without sleep profoundly limits the ability to think, especially executive functions such as multitasking, remembering details, and paying attention. This level of sleep deprivation can make it difficult to see even simple tasks through to completion.
Emotions are also affected. People who have undergone this level of sleep deprivation may be easily irritated. They may experience a depressed mood, anxiety, or paranoia. Research has also found that sleep deprivation makes it more difficult to process others’ emotions. In one study, participants with 30 hours of sleep deprivation had difficulty recognizing angry and happy facial expressions.
Several days of sleep deprivation can also significantly alter perception. You might experience hallucinations, which occur when you see something that isn’t there. Illusions are also common at this time.
Not sleeping can change both your appetite and the types of foods you crave. Studies suggest that sleep deprivation is associated with both an increased appetite and an increased desire for foods associated with weight gain. However, consuming empty calories can ultimately leave you more tired.
Eating well may offset some of the effects of sleep deprivation, but only to an extent. Since your body is conserving energy, opt for lean, protein-rich foods, such as nuts and nut butter, cottage cheese, or tofu. Avoid fatty proteins, such as steak or cheese. These will make you sleepier.
Dehydration can exacerbate the effects of sleep deprivation — such as grogginess and difficulty concentrating — so it’s also important to drink plenty of water.
Chronic partial sleep deprivation is when you don’t get enough sleep on a regular basis. It’s different than pulling an all-nighter once in a while. It’s also more common than missing one or two nights of sleep in a row, as most people are likely to sleep for at least a few hours per night. Chronic partial sleep deprivation is associated with both short-term health risks and long-term complications.
In some cases, sleep deprivation isn’t a choice. No matter how much we want or need to rest, our bodies simply aren’t having it.
A classic example of this is something called Morvan’s Syndrome. Subjects with this medical disorder were studied, and it was found out that people with this disorder sleep very little. Besides pain and sleeplessness, other symptoms of Morvan’s Syndrome include muscle twitching, sweating, and weight loss.
Up to 22 million Americans also may be suffering from sleep apnea. This disorder occurs when your airway becomes blocked, reducing or eliminating airflow. People with this condition can wake up several times per night, causing severe sleep deprivation if left untreated.
Restless Legs Syndrome (RLS) is a nervous system disorder that creates an uncontrollable urge to reposition your legs. It’s accompanied by uncomfortable tingling and twitching, commonly described as “pins and needles” or a “creepy-crawly” feeling. While this disorder is most common among middle-aged women, anyone can suffer from these symptoms.
Quality matters as much as quantity when it comes to sleep. Practicing good sleep hygiene can promote higher quality sleep. People can improve their sleep hygiene by taking certain actions that can lead to improved sleep quality and daytime alertness.
Sleep hygiene tips include maintaining a consistent sleep schedule by going to sleep and waking up at the same time each day, including at weekends. Removing electronic devices, such as smartphones, computers, and televisions, from the bedroom, also helps.