Americans have gotten fatter over the past 20 years, but options are available for those who want to combat obesity.

According to the Center for Disease Control and Prevention Web site, people with a body mass index greater than 30 are considered obese. Body mass index is a common measure expressing the ratio between a person’s height and weight.

Ten to 22 percent of Illinois residents were classified as obese in 2001, according to the CDC Web site.

Ellen Parham, a family, consumer and nutrition sciences professor, said changes in a person’s diet can help eliminate obesity.

“In order to lose weight, they need to have a negative calorie balance,” Parham said. A negative calorie balance means a person burns more calories than they take in.

Increasing physical activity will help prevent weight gain, Parham said.

“Think about what physical activity you enjoy doing,” Parham said. Also, Parham said she recommends eating a balanced diet and stopping when you feel full.

Dennis Wolf, owner of Seattle Sutton Healthy Eating in Sycamore, said there are ways to eat more healthfully which help to avoid obesity. He recommends eating low-fat and low-calorie foods, avoiding “super-sizing” meals if you eat at fast food restaurants and watching the portion size of meals at other restaurants.