The Body Mass Index, or BMI, is a calculated measure of the relationship of an individual's weight compared to height. Those with high values of BMI are classified as overweight or, at higher levels, obese. In addition to often limiting quality of life, obesity is a risk factor for many common illnesses including diabetes, high blood pressure, heart disease, strokes, arthritis and some cancers. As the graph shows, the prevalence of adults in northern, lower Michigan who are significantly obese has increased from about 17% to about 21% between 1995 and 2000.

This measure is considered one of Michigan's Critical Health Indicators. To view state data in this area, visit the Michigan Department of Community Health. Nationally, the Centers for Disease Control also track this statistic.