The pillow is a product of “civilization.” Sleeping with the head elevated allows our naturally curved spine to better maintain its natural curvature.
△ Ancient Chinese pillows， Daderot
To maintain good sleep quality over extended periods， keeping the spine in a natural state is essential. Otherwise， excessive pressure on spinal joints and surrounding muscles can lead to various musculoskeletal issues.
The curvature of our spine is closely related to upright walking. This curvature helps to better balance body weight， absorb shock， and support the head.
Due to this physiological structure， pillows can significantly enhance comfort and allow for a wider range of sleeping positions. With a pillow， many sleeping postures can ensure the spine remains in its natural alignment. Therefore， given the option， most people prefer to sleep with a pillow.
However， this absolutely does not mean that humans have evolved to *require* pillows for sleep. In fact， we can sleep perfectly well without them.
For instance， numerous indigenous tribes still exist on Earth today who do not use pillows and can sleep soundly without anything (including parts of their own bodies) to prop up their heads!
Research has documented how individuals in such pillow-less societies sleep. It has been observed that these people， living a more primitive lifestyle， experience very few muscle and bone-related problems. In contrast， over 90% of people who use pillows experience such issues at some point in their lives. This suggests a potential link between pillow use and the prevalence of musculoskeletal ailments.
Consider side-sleeping in the manner depicted. This posture requires no external support for the head and effectively maintains the spine’s natural alignment due to the natural bending of the lower shoulder， which provides excellent neck support.
Great apes like gorillas and chimpanzees exhibit similar sleeping positions:
An advantage of this sleeping position is that the mouth remains closed due to gravity， preventing insects or other small creatures from crawling in.
However， as noted by some researchers， people in indigenous tribes often dislike this position because it places their private areas close to the ground， increasing the risk of insect bites.
A simple adjustment to the sleeping posture can effectively address this issue. For example:
This side-sleeping position protects the private areas. Furthermore， it allows for the insertion of the Achilles tendon of the front leg into the space between the big toe and the little toe， which can help in correcting a bunion.
However， this position often requires using an arm as a pillow， which could lead to arm numbness after a prolonged period. It’s also possible that individuals in primitive societies did not require the extended sleep durations that modern humans often aim for.
Indeed， gorillas and chimpanzees also adopt this sleeping posture:
Building upon the protective side-sleeping posture， a slight adaptation can be made:
This position stabilizes the pelvis， rotates and flexes the spine， extends the elbows outwards， and places the chest against the ground. This posture has been termed the “quadrupedal reclining” position and also requires no head elevation.
Moreover， this sleeping posture not only aligns the spine naturally but also aids in correcting existing spinal injuries and may help in preventing relevant ailments.
Another notable sleeping position is as follows:
This posture， similar to the preceding one， utilizes an arm as a pillow and is adopted by some primates. Researchers have observed howler monkeys in Costa Rica employing this position， though photographic evidence is lacking.
Interestingly， humans can even sleep without lying down， for example:
This posture is commonly observed in children and can be adopted by adults， although most are simply unaccustomed to it.
In wilderness survival situations， this sleeping position is a practical choice when the ground is cold and damp. It significantly reduces the body’s contact with the ground. A photograph from 1938 shows Tibetan caravans adopting this sleeping method during long journeys.
We can also find examples of this sleeping posture demonstrated in wilderness survival shows by experienced explorers.
In conclusion， there are numerous effective methods for sleeping without a pillow， leveraging our flexible limbs to provide natural support akin to a pillow.
Furthermore， it is evident that certain pillow-less sleeping postures can be highly beneficial for regulating our muscles and bones， thereby reducing the incidence of related diseases.
