Marcella La Cioppa Short sleepers get four to six hours a night and don't seem to suffer any ill effects, and research suggests they're genetically engineered to need fewer hours of sleep.
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Everyone has heard the recommendation to sleep seven to nine hours a night—a guideline so frequently repeated that it feels like gospel. However, recent discoveries reveal a “rare breed” of individuals who thrive on significantly less sleep.
They are termed natural short sleepers because these people have genes that require just four to six hours of sleep in a day. This abnormality points out the fact that sleep quality might matter more than quantity. According to scientists, unraveling what makes these people special could help researchers gain essential information about sleep nature.
Until now, most people considered sleep just as time used to shut down a computer in preparation for a new day. Thomas Edison famously dismissed sleep as a “waste of time” and a relic of our cave-dwelling days, claiming he never slept more than four hours a night. His invention of the lightbulb even encouraged shorter sleep durations for others. Today, a record number of adults report getting fewer than five hours of sleep per night.
Modern research, however, paints a more complex picture. Sleep is now understood as an active and intricate process. During sleep, the body and brain replenish energy reserves, clear toxins, prune neural connections, and consolidate memories. Chronic sleep deprivation, as a result, carries significant health risks.
What the research says
Much of what we know about sleep comes from a model developed in the 1970s by Swiss-Hungarian researcher Alexander Borbély. His “two-process model of sleep regulation” explains how the circadian rhythm and sleep homeostasis interact to determine when and how long we sleep.
The circadian rhythm is our internal 24-hour clock, driven by external cues such as light and darkness, while sleep homeostasis reflects internal pressure that builds while awake and dissipates during sleep—similar to hunger and satiety cycles.
This knowledge developed with the discovery made by Dr. Louis Ptá ek and Dr. Ying-Hui Fu, research scientists at UC San Francisco who came across a woman who happened to wake naturally at early hours in the morning. The scientists concluded that her daughters’ unusual nature was passed onto their granddaughters, creating an opportunity to trace a rare genetic mutation linking the phenomenon.
Their curiosity deepened when they studied a family with a different pattern: early risers who needed only six hours of sleep yet felt fully rested. This group became the first identified cases of familial natural short sleep, linked to a mutation in the DEC2 gene.
Uncovering the genetics of short sleep
Over time, Ptáček and Fu’s team pinpointed seven genes associated with natural short sleep. In one family spanning three generations of short sleepers, researchers identified a mutation in the ADRB1 gene, which is highly active in the brainstem’s dorsal pons—a region critical for sleep regulation.
In a third father-son pair, mutation was identified in the NPSR1 gene, which plays a role in controlling sleep-wake cycles. And two different mutations in the GRM1 gene were identified in two separate families, each having short sleep cycles.
Interestingly, natural short sleepers appear not to suffer the ill effects of sleep deprivation. They are said to be enterprising, cheerful, and more resistant to stress, with increased pain tolerance levels. Some reports even indicate them to have greater longevity.
Toward a new model of sleep
Those results have convinced researchers like Ptáček that it’s high time to reassess the traditional two-process model of sleep. A third factor, known as “behavioral drive,” introduces him. In this newer version, it is the circadian clock that starts the day while sleep homeostasis tells him that he or she has slept enough. Behavioral drive, on the other hand, pushes him or her to be active; this behavioral activity should reverse at night, thus preparing the body for sleep.
While much remains unknown about how these genetic mutations enhance sleep efficiency or shield short sleepers from health risks, Ptáček and Fu are conducting further studies by monitoring brain waves in their lab.
Conclusion
For now, scientists emphasize the importance of tailoring sleep needs to the individual, as the “optimal” amount of sleep varies from person to person. Whether you’re a natural short sleeper or need the full eight hours, understanding your body’s unique requirements is key to maintaining overall well-being.
Source: NIH
