The prevalence of periodontal disease among obese individuals aged 18-34 years was 76% higher than normal weight individuals in this age group. Obesity can in fact cause inflammatory phenomena in the gums. This will eventually lead to gum disease and affect your teeth, causing them to become more and more lose over time.
The size of our waist, and our dental health, hold a closer relationship than we ever thought possible. The more teeth you are missing, the worse it could potentially become. Missing a number of teeth typically means poor distribution of masticatory forces, and if something isn't done to remedy this problem, people with missing teeth will continue to gain weight. The reason for this is chewing, as missing teeth causes one to chew improperly and eat softer foods such as fats and starches (many times for comfort reasons). These foods are more likely to be eaten than healthier choices, such as apples, which are much harder in texture and more difficult to chew (when compared to something high in fat like potato chips).
Many studies have also shown that not just missing teeth, but tooth decay, might also be a major problem. These studies have demonstrated a correlation between the presence of tooth decay and being overweight or obese. People with tooth decay, it seems, tend to eat more sweets and snack foods. Both of these "junk food" types are known to put on the pounds, and, cause tooth decay.