Following up on theories of a relationship between obesity and gum disease, researchers at the School of Dental Medicine of the University at Buffalo examined data from the Third National Health and Nutrition Examination Survey (NHANES III) and found that overweight people with the highest levels of insulin resistance were 50 percent more likely than overweight people with low levels of insulin resistance to have advanced periodontal disease.

The research, funded by a grant from the U.S. Public Health Service, analyzed data on the extent of periodontal disease, body mass index (BMI), fasting blood insulin levels, and fasting glucose levels for 10,836 participants who participated in the NHANES III survey. Individuals with diabetes and those with less than six teeth were excluded. Persons with a BMI of more than 27 were considered overweight, and the index of insulin resistance was determined by multiplying the level of fasting insulin by the amount of fasting glucose circulating in the bloodstream.

The analysis found that overweight people with an insulin resistance index in the top quartile were nearly 50 percent more likely to have severe periodontal (gum) disease than those with high BMIs and low levels of insulin resistance. This relationship is meaningful because obesity is a risk factor for type 2 diabetes and heart disease. It is possible that periodontal disease contributes to serious health consequences in overweight individuals, such as elevated low-density lipoprotein (LDL) and total cholesterol levels.

The results of the study were presented at the April 8, 2000, annual meeting of the International Association for Dental Research. The lead author of the study says that molecular biology-based studies are needed to determine the mechanism and biological basis of the obesity-periodontal disease relationship.