These bacteria love those proteins, and certain foods are packed with them: Milk and Cheese and most other dairy products. (The fat content does not matter.) If you are lactose intolerant, do not eat or drink these products! Since your system cannot digest them properly, they are available to the bacteria for an extended period of time. Fish are high in proteins. As many people eat a high fish diet, logically they make the problem worse. Coffee with caffeine (and even without) contains high levels of acids which cause the bacteria to reproduce more rapidly and create a bitter taste for many people. (Virtually any acidic type of food will do this.)