Drinking coffee regularly needs to consider the benefits and risks brought by caffeine. The effect of caffeine is related to weight sensitivity. Caffeine is a stimulant of the central nervous system. Besides losing weight, most people can stay awake and refresh themselves by drinking coffee. The side effects of long-term drinking include insomnia, rapid heartbeat, gastrointestinal discomfort, elevated blood pressure, migraine, nervousness, anxiety, tinnitus, muscle twitching, frequent urination, dehydration (especially after exercise) and calcium loss. Sensitive people will have the above performance even if they drink a small cup or two cups of coffee. Drinking coffee for a long time may lead to tolerance and even dependence. If caffeine is suddenly stopped, severe headache, muscle pain, depression, irritability, constipation and other withdrawal symptoms may occur. In order to relieve withdrawal symptoms, most people will fall into a vicious circle of drinking more and more. Use caffeinated drinks with caution in the following situations: insomnia; Stomach discomfort, such as gastric ulcer, gastroesophageal reflux, heartburn and flatulence (hypersecretion of gastric acid); Diarrhea and irritable bowel syndrome (increased intestinal peristalsis, aggravating diarrhea); Patients with glaucoma (elevated intraocular pressure); Hypertension (hypertension) patients; Heart disease patients. If healthy adults have the habit of drinking coffee, it is recommended to drink caffeinated drinks in moderation, that is, 100-200mg/ day. Most healthy adults consume less than 400 mg of caffeine every day, which is considered as a safe dose. The daily caffeinated beverage content, a Starbucks mug contains about 330 mg of caffeine, and an 8 oz (about 235 ml) cup of freshly brewed coffee contains about 133 mg of caffeine. In addition, pregnant women should not consume more than 200mg of caffeine every day, which is equivalent to two cups of instant coffee. The wet nurse does not exceed 1-2 cups of coffee every day.