Sleepy after eating is caused by relative ischemia and lack of oxygen to the brain after meals, which is a normal physiological phenomenon, and the symptoms can disappear after the food is digested in the stomach. Food into the stomach signals, so that a large amount of blood in the blood circulation is distributed to the digestive tract to help digest food, while the brain blood supply is relatively reduced, which leads to brain ischemia, lack of oxygen, which will make people sleepy. In addition, after eating full will lead to increased blood viscosity, blood flow is slow, will further cause brain ischemia, lack of oxygen, so that people are more likely to sleepy. This kind of sleepy after eating is dangerous for the elderly, especially patients with atherosclerosis and cardiovascular disease, which can easily lead to cardiovascular disease or aggravate the condition. Therefore, it is recommended that the plain diet seven or eight percent full, even if sleepy after meals do not immediately sleep, it is best to take a walk half an hour after meals, which can promote blood circulation, help digestion, and is conducive to good health.