There are two main reasons for dizziness after eating: First, after eating, a large amount of blood enters the digestive tract to digest and absorb food, resulting in insufficient blood supply to the brain and symptoms of dizziness, commonly known as food sleepiness, usually pay attention to a light diet, each meal is not too full, eat less large fish and meat, after eating can be appropriate activities. Second, sympathetic nerve dysfunction, under normal circumstances when eating sympathetic nerve is in a state of excitement, so that there is an increase in blood pressure, to prevent insufficient blood supply to the brain. Patients with sympathetic nerve dysfunction can experience a decrease in sympathetic excitability after eating, and a drop in blood pressure after eating, leading to symptoms of dizziness.