It's possible for other health conditions and habits to affect your breath. Halitosis may occur in people who have a sinus or bronchial infection, an oral yeast infection (which can be caused by antibiotic use), or even a systemic (general body) disease such as diabetes, kidney failure or a liver malfunction. A chronically dry mouth (xerostomia), which is often a side effect of certain medications, and tobacco use can also contribute to this problem. Even stress, dieting and hormonal changes can affect your breath.