Earlier research has shown that eating fast food contributes to weight gain because of enormous portion size, high energy density, excessive amounts of refined starch and added sugars, high fat content and low levels of dietary fiber — it also tastes good.
Eisenson says that the health risks to obese children and teenagers are enormous. "They develop diabetes at a younger age, they develop the complications of diabetes at a younger age, they develop the risk factors for heart disease at a younger age. Basically, they have impaired function and impaired quality of life."
And even though the study showed that lean teens aren't as vulnerable to gaining weight from eating fast food, their health is still at risk.
"Even lean kids are getting fewer vegetables and whole grain foods," says French. When you eat fast food, "you are displacing these more healthful foods."
Fast Food Industry
The fast food industry does need to take responsibility for their part of the picture, at least by limiting the marketing of products to children, some argue.
Michael Jacobson, executive director for the Center for Science in the Public Interest, says that the public health measures may be warranted to limit fast food consumption in children.
"'Limit in two ways," says Jacobson. "Get typical fast food out of schools, limit marketing efforts aimed at youths, and improve the foods [less salt, saturated and trans fat: greater availability of whole grains, fruits, veggies, etc.] as much as possible so that even kids who won't make wise choices will be protected to some extent."
However, Michael Goran, professor and associate director of the Institute for Prevention Research, Department of Preventative Medicine, University of Southern California, is not in favor of limiting fast food.
"I am not a big fan of limiting stuff because we know that can turn negative," says Goran. "Although the fast food companies are doing a better job of making healthier choices available, these tend to be marketed to adults. We need to find better ways to market healthier choices to kids and make them just as appealing."
Laurie Tansman, nutrition coordinator in the Department of Clinical Nutrition at Mount Sinai Hospital in New York City, is optimistic about the role the fast food industry has already taken in America's obesity crisis.
"I think that there is no question that the fast food industry — and the food industry in general — is being more aggressive in their response to the public's concern to overweight and obesity," says Tansman.
For its part, the National Restaurant Association said: "This study unfairly targets the quickservice industry and, as the study's title suggests, is primarily focused on energy intake. There is no reference to today's sedentary society and the lack of physical activity and physical education programs in our children's schools."
Yet many others believe that the fast food industry has a long way to go; fast food restaurants are everywhere and it's heavily marketed to children and teenagers.
"If the fast food industry is serious about helping with the obesity epidemic, there are steps they can do to help people make healthy choices," says French. "People often believe that individual choice matters, but people's choices are shaped by the incentives and information in their environment."
Eating out is becoming a danger zone for people who have a tendency to gain weight.
Eisenson warns, "It's almost like we should put a sign out that says, 'People who struggle with weight issues should eat here at their own risk.' "