How much coffee you drink every day can harm your body depends on the caffeine content inside the coffee, and it is generally recommended that the daily caffeine intake of an adult should not exceed 400 mg, i.e. about 3 cups of coffee. Coffee is a nutritious beverage, mainly containing fat, protein, sodium, potassium, hydrochloric acid and caffeine. Moderate consumption is beneficial to human health. However, excessive consumption of the caffeine contained in coffee can cause some damage to the body. Therefore, it is recommended that the daily caffeine intake of adults should not exceed 400 mg. According to the calculation of American-style coffee, 400 mg of caffeine is equivalent to three cups of about 150 ml of coffee, and there are obvious individual differences. In addition, coffee is not recommended for pregnant women and children. Coffee should be consumed in moderation, and if symptoms of physical discomfort occur, go to the hospital for examination and treatment.