Normal healthy people drink coffee in moderation to reduce fatigue and refresh the brain. Occasionally, too much coffee can inhibit the normal activity of the brain nerves due to excessive caffeine intake, resulting in difficulty sleeping, insomnia, excitement and other neurological symptoms, as well as accelerated heartbeat, palpitations, dizziness, sweating and other cardiovascular and cerebrovascular symptoms. However, no special intervention is usually required, and the symptoms will disappear after coffee is metabolized and discharged in the body. For special groups of people, such as insomnia, stomach acidity, gastric ulcers and other patients, drinking too much coffee can cause symptoms to worsen. Studies have shown that caffeine in coffee can act on the urinary system to promote urination, on the digestive system to stimulate excessive secretion of gastric acid, which can lead to chronic gastritis in the long term, and on the nervous system to aggravate the symptoms of insomnia. At the same time, the additive hydrogenated vegetable oil in coffee can increase the cholesterol content in the blood, increasing the probability of cardiovascular disease. If a pregnant woman consumes too much coffee, it can lead to an increase in the chance of miscarriage. Caffeine can also enter the placenta through the mother’s blood and be transported to the fetus, affecting fetal development and even malformations. In addition, excessive coffee consumption is not good for the health of the body, and can even cause autonomic dysfunction, causing dizziness, headache, panic, shortness of breath, arrhythmia and other symptoms, and in serious cases, heart disease, long-term consumption may also aggravate the symptoms of depression patients. Therefore, long-term, excessive coffee consumption should be avoided.