People with fragile gastrointestinal tracts are not recommended to drink coffee on an empty stomach. Coffee contains a large amount of caffeine, will cause stimulation of the gastric mucosa, causing gastric acid secretion, gastrointestinal tract is fragile people may appear epigastric discomfort, nausea, vomiting and other symptoms, so fasting is not recommended to drink coffee. Patients suffering from gastritis, gastric ulcer and other diseases drinking coffee on an empty stomach may lead to aggravation of the condition. Those with normal gastrointestinal function and good tolerance to caffeine in coffee can drink coffee on an empty stomach as appropriate. Pay attention to moderation when drinking coffee and avoid drinking a large amount at one time. Pregnant women, lactating women, children, and insomnia patients are advised to drink coffee with caution.