Short Sleepers: Why Don’t They Need Sleep?

Imagine a world where you hardly ever went to sleep. For short sleepers, this is their reality. For most people, it would result in severe sleep deprivation, but for others, it’s nothing out of the ordinary. These individuals are short sleepers, a term which defines people who can function with less than a ‘normal’ amount of sleep or rest for his or her age group without known adverse effects.

If you think you could be a short sleeper, or know somebody who could be, here we explore short sleeper syndrome. We’ll look at scientific research to understand why they don’t need sleep and the effects of getting little sleep.

To date, only a handful of small studies have looked at short sleepers. Those who are short sleepers are unlikely to go to sleep clinics as they are not aware that they have a disorder.

Dr. Christopher Jones, professor of clinical neurology at the University of Utah, says he has only identified about 20 true short sleepers, and he says they share some fascinating characteristics.

Short sleepers’ circadian rhythms (the body’s daily biological cycles) are different from most people’s, their moods are upbeat, and they’re thinner than average – even though sleep deprivation usually raises the risk of obesity. They also seem to have a high tolerance for physical pain and psychological setbacks.

Some short sleepers can sleep as little as four hours per night and function normally. According to the Sleep Need Consensus Statement in June 2015, the average human should sleep seven or more hours per night on a regular basis to promote optimal health, but what happens if you think you are a short sleeper when you’re not? You become sleep deprived.

Studies have shown that if you don’t have enough sleep and you are not a short sleeper you can put on weight and are more likely to suffer from diabetes and cardiovascular disease.

For example, Prof. Dinges and his team carried out a study with 194 people in their lab for five nights and only allowed them four hours of sleep. Another group was in the lab for just as long and they got ten hours of sleep in bed at night. The 194 people who had their sleep restricted gained a kilo of weight during the five days and weren’t aware of the fact that they were mindlessly eating fatty foods at a higher rate.

Prof. Dinges explained: “This a phenomenon that many people experience. They stay up at night craving something to eat but they don’t go and eat something healthy, such as fish. They go out and eat high-fat food. So, we know there is biology here that people are not entirely aware of.

“We don’t know for sure why those who are sometimes resistant to sleep loss are not the short sleepers, and why short sleepers will nevertheless be susceptible to sleep loss.”

Prof. Dinges explained: “That’s a question that many sleep physicians pay close attention to. If you ask someone, ‘how sleepy are you?’ That’s not very effective. Even if you give them a scientific scale to rate themselves, it doesn’t work very well. So what many physicians do around the world is ask the patient ‘have you ever fallen asleep driving or watching the TV?’ If someone reports that all those things happen to them, and not infrequently, that is usually seen by the physician as excessive sleepiness to the point of even being related to a medical condition.

“The problem is some won’t be asked those questions and instead, if they are just sleepy from lifestyle, they tell everyone they’re not sleepy, but that’s because when they are talking about it they are being socially stimulated.

“The diagnosis is simple – if you cannot stay awake in a meeting, a comfortable chair, conversing with someone, a classroom, driving a car; If your eyelids are closing, your head’s falling over, you’re struggling to stay awake, you are yawning, you’re fighting it – then you’re sleep-deprived.”

We hope you found this helpful. If you think you may not get enough sleep, get in touch with your GP for guidance.