For some people with lower-back pain, placing a small pillow beneath the knees reduces tension in the lower back and makes it easier to relax.
It may reduce pressure on the shoulders and hips.
Side sleeping places more direct pressure on the shoulder and hip against the mattress. Back sleeping can reduce this pressure for people who find those areas uncomfortable.
However, individual results vary. People with certain shoulder, neck, or spinal conditions may find back sleeping less comfortable.
It avoids prolonged head rotation.
Unlike stomach sleeping, back sleeping does not require the head to remain turned to one side for breathing.
This can be helpful for people whose neck discomfort is aggravated by sustained rotation.
Why back sleeping may be unsuitable for some people
The most important limitation is its effect on breathing.
For some people, particularly those with obstructive sleep apnea, lying on the back can allow soft tissues in the throat to narrow the airway. This may increase snoring and breathing interruptions.
