So concludes new research in the January/February issue of the American Journal of Health Promotion.
The two-year study included nearly 200,000 General Motors workers. It found the average annual medical costs for people with normal weight was $2,225, compared to $2,388 for overweight people and $3,753 for people who were the most severely obese.
The study found that 40 percent of the GM workers were overweight, 21.3 percent of them were obese, 37 percent had healthy weights and 1.5 percent were underweight.
This is the first study to examine the relationship between medical costs and the six weight groups outlined in the U.S. National Heart, Lung, and Blood Institute's weight guidelines.
The researchers say their findings show the economic burden caused by obesity. In 1994, it was estimated that the direct medical costs of obesity in the United States total $51.6 billion. Being overweight and obese leads to many chronic diseases.
Here's where you can learn more about obesity.