Jay Summer is a health content writer and editor. She holds a B.S. in psychology and master's degrees in writing and public policy.
Many people have wondered if their preferred sleeping position reveals aspects of their personality. Very little scientific research about sleep positions and personality traits exists, and recent studies find a tenuous connection between the two. Although there is some research linking sleep position and personality, study methods and definitions of different sleeping positions vary widely, and thus far researchers are unable to convincingly explain the logic behind the connection.
Despite the lack of rigorous research on sleep position and personality, contemplating your preferred positions could still be interesting and useful. Research about sleep position can provide helpful insights into your health and sleep, as people often consciously or unconsciously adopt certain sleeping positions to help relieve uncomfortable symptoms.
The definition of each sleeping position changes from study to study, but most researchers speak of side, back, and stomach sleeping, and divide each of these broad categories into several variations.
Children spend equal amounts of time in all three sleeping positions: side, back, and stomach. As people age, however, they spend more time sleeping on their sides. Exact numbers vary, but studies show that on average, over 60% of adults spend the majority of the night in a side position. Older age and a higher body mass index are both associated with more side sleeping.
There are multiple variations of the side sleeping position. Over time, researchers have posited that different side sleeping positions correspond to different personality traits. Since there is not recent peer-reviewed research available to support these claims, they should be taken lightly.
The fetal position gets its name from the shape of a baby in the womb. In the fetal position, a sleeper’s body is essentially curled up into a ball as they lie on one side with legs and arms bent. This position is commonly assumed by adult sleepers.
In the 1970s, sleep researcher Samuel Dunkell was the first to hypothesize that the fetal position corresponded with certain personality characteristics. Through his research, Dunkell observed that fetal position sleepers tend to be more anxious and emotional. This was in contrast to the semi-fetal position, whose adherents he described as being well adjusted. Researchers Domino and Bohn in 1980 found similar results, but researchers in 2002 and 2012 were not able to draw the same conclusions.
A contemporary sleep researcher, Chris Idzikowsk says his research has also shown fetal position sleepers can be shy around new people, but relax fairly quickly. This research shouldn’t be taken as the final word, since it has not been peer-reviewed.
Although the log is another side sleeping position, it differs quite a bit from the fetal position. While assuming a log position, a sleeper has both their arms and legs extended, so their body is straight like a log. Surveys suggest the log as being a common position, while other research suggests that a true log side sleeping position is uncommon. This study found that many sleepers extend both legs while sleeping on their sides, but most keep at least one arm folded.
Sleep scientist Idzikowski claims that preferring a log position suggests that a person is sociable and interacts with others easily. While these are attractive traits, he warns that this openness and willingness to trust could make them gullible.
In the yearner position, a sleeper looks like they are reaching or yearning for something. Their legs and arms are both outstretched, like in the log position. The difference is that instead of being by their sides, their arms extend forward.
According to research by Idzikowski, people who prefer the yearner position tend to be open, though not as open as those who prefer the log position. Yearners can also be cynical and suspicious. That said, these assessments should not be taken too seriously. This research has not yet been peer-reviewed or replicated by other researchers.
Side sleeping offers many benefits, such as less snoring in people with and without obstructive sleep apnea and a potential reduction in back and neck pain. Sleeping on your left side decreases symptoms of gastroesophageal reflux disease (GERD) and is recommended for a healthy pregnancy, especially in the second and third trimesters. Sleeping on the right side is the preferred position for people with heart failure.
Side sleepers generally require thicker pillows than back and stomach sleepers, in order to keep the head aligned with the rest of the spine. For side sleepers, a medium to medium firm mattress can help support heavier parts of the body without causing pressure buildup at the hips and shoulders. If you experience shoulder pain, you might want to avoid sleeping on the side in which you feel pain.
The back sleeping position is the second most popular position, after side sleeping. One study found that, on average, over one-third of sleeping time is spent on the back. Based on his 1970s research, sleep researcher Dunkell claimed that people who sleep on their backs are more self-confident. Dunkell also said back sleepers are likely to be more open and sensation-seeking than other sleepers.
There are multiple ways to sleep on your back. Two postures in particular have received attention from sleep researcher Idzikowski. These are the soldier and the starfish.
In the soldier position, you lie as straight as a soldier stands. The legs are not bent, and your arms lie straight along the sides of your body. Idzikowski claims soldier sleepers are quiet and reserved, but also hold high standards.
When sleeping like a starfish, you lie on your back with arms up near the pillow and legs outstretched. Idzikowski says starfish sleepers value friendship, and that while they prefer not to be the center of attention, people who sleep in this position are good listeners and quick to help others.
Depending on the nature of the pain, some individuals may find that back sleeping helps alleviate pressure points. Since your face is not usually pressed against the pillow while back sleeping, this position may also help prevent wrinkles. Although back sleeping can trigger acid reflux when a person is lying flat, symptoms are reduced in those who sleep on their back with the head of the bed elevated.
If you prefer sleeping on your back, try to do so symmetrically to avoid back pain. Keeping one arm up and one down can strain your neck and shoulders, especially if one arm is at a sharp angle. The best mattresses for back sleeping provide adequate lumbar support, so your lower back doesn’t arch unnaturally as you sleep. You should also find a supportive pillow that allows your neck to retain its natural curve and stay aligned with your spine.
Of all sleep positions, stomach sleeping is the least popular and by older adulthood, very few people sleep on their stomachs. This shift in sleep position habits could be due to a lack of flexibility. Stomach sleeping puts pressure on the spine, which can lead to increased back and neck pain upon waking.
Sleep researcher Dunkell posited that stomach sleepers tend to be anxious, impulsive, compulsive, and rigid, traits he said work well for jobs in accounting, banking, and management. Similarly, researchers in 1980 and 2002 found that stomach sleepers were more likely to be anxious and less self-confident.
Results from a study in 2012 did not support these findings. Sleep researcher Idzikowski also has a different take on stomach sleepers, particularly those who adhere to the freefall position.
In the freefall position, a stomach sleeper has their hands on or around their pillow, with their head turned to one side. Idzikowski claims his research shows that freefall sleepers are social and can border on being brash. Deep down, however, they are more sensitive and can become unsettled by criticism or extreme situations.
In addition to straining the back and neck, sleepers may find that breathing requires extra effort when lying on their stomach. If you experience back or neck pain and regularly sleep on your stomach, you might want to consider switching to back or side sleeping, or changing your bed setup to reduce spinal strain.
Stomach sleepers tend to require a firmer mattress and a pillow with a low loft. A mattress that is too soft can result in spinal misalignment, and a pillow that is too lofty or firm can put pressure on the neck and lead to stiffness.