Does diabetes cause bad breath? The answer is unequivocally yes. Diabetes, a chronic metabolic disorder, can significantly impact oral health, often resulting in persistent bad breath, medically known as halitosis. This unpleasant condition arises due to several interrelated factors. Elevated blood sugar levels create an environment conducive to bacterial growth in the mouth, while the presence of ketones—a byproduct of fat metabolism in poorly controlled diabetes—can produce a distinctive, fruity, or acetone-like odor.Â