Gums U.S. government researchers said in late May that smoking increases the risk of periodontal (gums) disease by four times. They said in their report that in half of periodontitis cases among U.S. adults, smoking is a major risk factor. Accordingly, smoking causes a deterioration of gums by reducing the delivery of oxygen and nutrients to gingival tissue, and impairs the body's defense system, making smokers more susceptible to an infection like periodontal disease. Scientists have said recently that periodontal disease is linked to more serious illnesses like heart disease, diabetes and respiratory ailments.