Yes, persistent bad breath may be a byproduct of other medical conditions. Common ailments like acid reflux and heartburn could leave a bad taste in your mouth. In other cases, bacteria and mucus buildup from a sinus infection could be what’s causing the issue. Slightly fruity breath that isn’t wholly pleasant or offensive is a telltale sign of diabetes, while a strong, ammonia scent has been linked to kidney disease. Periodontal diseases like gingivitis can cause bad breath because of the presence of excess bacteria in the mouth. And dry mouth, which causes a decrease in saliva, leaves your mouth unable to naturally flush bacteria and food particles from your teeth and gums before they break down and start to decay. If you’re worried your bad breath might be a sign of a bigger issue, or if you’re just unable to tame it yourself by brushing, flossing and rinsing, talk to your dentist.