Sleeping without a pillow is not good, if you do not sleep with a pillow, the physiological curvature of the neck will be deformed, and the normal physiological curvature of the human body will disappear. The human 2nd-7th cervical vertebrae need to be physiologically protected, not when the pillow will appear cervical spondylosis, especially cervical disc herniation, disc bulge, so patients with cervical spondylosis do not pillow will appear arm numbness, pain, etc.. If you do not sleep on a pillow for a long time, it will also cause the head position low, the heart position high, the blood after the operation of the heart will be a lot of influx into the head, resulting in the next morning up facial swelling, eyelid swelling, dizziness, brain swelling, abnormal expansion of cerebral blood vessels, so do not sleep on a pillow is not good for the human body. Patients with cervical spondylosis or cervical spine trauma can sleep with a relatively thin pillow, but not sleep without a pillow.