Getting enough sleep has always been considered one of the keys to good mental and physical health. However, researchers have discovered that some people, unlike the majority, are genetically predisposed to sleep less without feeling any less energetic.
Average Sleep Duration in People
While it may seem that sleep is a “waste of time,” intentionally depriving oneself of it can be detrimental to health. Yet, the question of what constitutes the right amount of sleep remains a topic of much debate.
Some scientists argue that sleeping less than six hours reduces the benefits of physical exercise. However, recent studies indicate that the duration of healthy sleep can vary based on genetics.
Adequate sleep is vital for well-being and sound judgment. However, the necessary duration can significantly differ depending on age, lifestyle, and overall health. According to the National Sleep Foundation, the following guidelines can be used as markers for healthy sleep:
- Newborns (0-3 months) – 14-17 hours daily;
- Infants (4-12 months) – 12-16 hours;
- Toddlers (1-2 years) – 11-14 hours;
- Preschoolers (3-5 years) – 10-13 hours;
- School-age children (6-12 years) – 9-12 hours;
- Teenagers (14-18 years) – 8-10 hours;
- Young adults (18-25 years) – 7+ hours.
It’s important to note that these are merely recommendations. Everyone is unique, and the amount of sleep needed can vary. Researchers also point out that sleep needs can change throughout the year, month, and even day, depending on how much rest a person requires to recharge their body and mind.
Factors that can influence this include levels of physical activity, stress, diet, and overall health. Moreover, sleep quality is just as crucial as its duration. Insomnia can significantly diminish the health benefits of a good night’s rest.
Why is Sleep Important?
Sleep has a long evolutionary history. It is believed that the systems regulating sleep may have first developed in oceanic creatures as a way to manage the timing of surfacing for food.
Today, sleep plays a vital role in nearly all animals (even jellyfish and worms). However, even bacteria, which do not sleep in the conventional sense, exhibit periods of reduced activity similar to sleep.
In higher organisms, sleep is more developed and consists of various stages and types. For instance, some mammals, birds, reptiles, and fish experience rapid eye movement (REM) sleep, which is associated with dreaming and supports learning and memory processes.
For animals with large brains and humans, sleep plays a crucial role in memory consolidation, as it helps the brain process and store new memories from the day. Sleep also supports cognitive functions such as creativity, problem-solving, and attention, while insomnia can hinder these abilities.
Sleep is especially important for children and teenagers, as it is a critical aspect of growth and development. During sleep, the body produces hormones that promote growth and help build muscle.
What Happens If You Don’t Get Enough Sleep?
Lack of sufficient sleep can negatively impact overall health. Insomnia leads to cognitive dysfunction, memory problems, and a weakened immune system. Insufficient sleep disrupts hormonal balance, leading to weight gain and obesity.
Sleep deprivation can result in irritability and mood swings, as well as an increased risk of chronic health issues. Overall, this contributes to a diminished quality of life. However, some rare individuals can function well while sleeping significantly less than the rest of the population.
Why Can Some People Sleep Less?
The secret seems to be encoded in their genetic makeup. For example, American scientists have identified a specific set of genes that contribute to “naturally short sleep.”
As noted by Interesting Engineering, it is this genetic code that allows some people to sleep just 4-6 hours each night throughout their lives without any adverse health effects. They feel just as energetic as those who have had a full night’s rest.
Typically, factors that disrupt sleep make it challenging for researchers to distinguish between those who naturally sleep less than six hours and those who rely on artificial stimulants to do so. However, in 2009, Professor of Neurology Ying-Hui Fu discovered that some people can cope with insufficient sleep due to a peculiar mutation in the DEC2 gene. According to her research, individuals without this “mutation” averaged 8 hours of sleep per night, while participants with it averaged about 6 hours.
Moreover, studies show that these natural “short sleepers” gain other advantages from this biological trait. They tend to be more optimistic, energetic, and effective at multitasking.
However, DEC2 is not the only genetic mutation linked to this “superpower.” Another group of researchers found a similar phenomenon in individuals with mutations in another gene, BHLHE41. People with this mutation not only enjoy shorter sleep without health drawbacks but also have a higher pain threshold and do not experience jet lag.
Some studies even suggest that they may live longer. The exact reasons for these advantages remain unknown. However, Dr. Fu’s work is an important step toward understanding the connection between good sleep and overall health. Of course, “short sleepers” are intriguing as a subject of research, but lacking this gene should not lead anyone to compromise their health by consistently sleeping only a few hours each night.