It is best not to drink overnight coffee. When brewing freshly ground coffee, milk is sometimes added, and milk contains protein, which is one of the components that are very easy to be moldy or even corrupt. So after drinking moldy milk and coffee the next day, it is easy to have gastrointestinal problems such as diarrhea.

American coffee is a kind of coffee and the most common coffee. It is made of black coffee, which is made of drip coffee pot or concentrated in Italy by adding a lot of water. American coffee tastes mild. Because the general extraction time is relatively long (about four or five minutes), the caffeine content is high.