Experts on cerebral thrombosis investigated 2,000 patients with cerebral infarction and found that over 95% of them were accustomed to lying on their side. As a result, in the case of already having arteriosclerosis, the blood flow obstruction was exacerbated, especially the blood flow speed in the neck slowed down, making it easy for blood to gradually accumulate at the site of arterial intimal injury and form thrombi. To eliminate this hidden danger, it is more appropriate to switch to sleeping on the back. Middle-aged and elderly people with emphysema should lie on their backs, raise their heads, and slightly stretch their hands upwards to keep breathing unobstructed. Patients with gastric diseases and ulcers are advised to lie on their left side. If you lie on your right side, the amount of acidic fluid flowing back from the stomach to the esophagus is much greater than normal and continues, which can cause stomach pain. For people with hypertension, it is advisable to sleep in a supine position with a pillow. The pillow is generally about 15 centimeters high; both too high and too low pillows can cause discomfort. For patients with heart disease whose compensatory function is still good, they can lie on their right side to reduce the pressure on the heart. If heart failure has already occurred, a semi-recumbent position can be adopted to alleviate breathing difficulties. It is strictly forbidden to lie on the left side or prone. Patients with acute or chronic liver diseases, gallstones and other conditions should lie on their left side, which is beneficial for their improvement.