If your morning breath seems to last all day, you may not be drinking enough water. Keeping your mouth moist helps wash away food particles and bacteria, which helps keep bad breath at bay. Chewing gum (preferably sugarless) or sucking on candy (again, sugarless) can help, too. If you have chronic dry mouth, your dentist or doctor may recommend an artificial saliva preparation or an oral medication that stimulates the flow of saliva.