How Much Sleep Can a Person Stay Awake? Health Effects of Sleep Deprivation
Explore the famous 1964 stay-awake study, the health risks of sleep loss, and science-backed guidelines for how much sleep people need at different ages.
Intro: Sleep is essential for health, mood, and daily performance. This article reviews what happens when you miss sleep, the famous 1964 stay-awake study, and evidence-based guidelines on how much sleep people need across life stages.
What happens when you don’t sleep
There is no safe limit to staying awake for long periods. The best-known case is the 1964 experiment by Randy Gardner, a 17-year-old from California, who stayed awake for 264 hours (11 days). The study was carefully documented to test whether extended wakefulness could occur without lasting harm.
Gardner and his clinician reported few major problems during the experiment, and Gardner even beat an opponent at table tennis near the end. However, another observer noted growing difficulties with attention, memory, speech, and even occasional hallucinations as time passed. Later reviews concluded that sleep deprivation is harmful, and Guinness World Records does not officially recognize such feats as valid records.
What happens to the body and mind when you don’t sleep
Insufficient sleep reduces quality of life and raises the risk of serious health problems. Even with a healthy diet and regular exercise, persistent sleep loss harms health.
In the short term, lack of sleep can worsen mood, impair concentration and memory, slow thinking, and cause microsleeps—brief episodes of sleep that last a few seconds to a minute. Microsleeps are particularly dangerous during activities like driving. The U.S. Centers for Disease Control and Prevention (CDC) estimates that drowsy driving contributes to about 6,000 deaths each year.
Chronic sleep deprivation is even more dangerous. It can affect nearly every system in the body and lead to issues such as:
- High blood pressure
- Type 2 diabetes
- Heart attack
- Stroke
- Depression
- Lower libido
- Weight gain
- Weakened immune system
How much sleep do people need?
The National Sleep Foundation in the United States provides age-based guidance on ideal sleep durations:
- Newborns (up to 3 months): 14–17 hours
- Infants (4–11 months): 12–15 hours
- Toddlers (1–2 years): 11–14 hours
- Preschoolers (3–5 years): 10–13 hours
- School-age children (6–13 years): 9–11 hours
- Teenagers (14–17 years): 8–10 hours
- Adults (18–64 years): 7–9 hours
- Older adults (65+ years): 7–8 hours
Note: Individual needs vary. Some people may feel rested with a little more or less sleep than these ranges.
Expert comment
Expert comment: Sleep researchers emphasize that while a single night of poor sleep can be recovered, persistent sleep loss increases risks for heart disease, diabetes, and mood disorders. Prioritizing regular, quality sleep is essential for safety and overall health.
Summary
Sleep deprivation affects mood, attention, and daily performance, and long-term lack of sleep raises major health risks. While one night of poor sleep can be recovered from, chronic patterns require changes in daily habits. Prioritizing sleep improves mood, safety, and long-term health.
Key insight: Regular, sufficient sleep is essential for health, sharp thinking, and safer living on the road.