Coffee can be drunk before and after meals. There is no special time limit or requirement for drinking coffee, which is decided according to one’s living habits, working and studying time. Coffee contains a large amount of caffeine, which can excite the central nervous system, and play a role in refreshing the mind and lifting the spirit. For people who study and work in the office, it is more suitable to drink coffee at three to four o’clock in the afternoon, when the body is in the stage of fatigue and easy to doze off, if you can drink a cup of warm coffee, it can relieve fatigue and improve study and work efficiency. For people with sleep disorders are not allowed to drink coffee before going to bed, otherwise it will cause insomnia to worsen. Coffee either before or after meals, if there is an adverse reaction, you need to consult a doctor in time.