June 15 (Bloomberg) -- All teenagers are likely to overeat a ``supersized'' fast-food meal and overweight children are the least likely to compensate for the calorie overload by eating less the rest of the day, according to a study in the June 16 Journal of the American Medical Association.

The findings show how fast food contributes to the obesity epidemic in industrialized nations and help explain why some adolescents are particularly susceptible to the high-fat, calorie- laden meals popular at restaurants such as McDonald's, Taco Bell and Kentucky Fried Chicken, the researchers said.

Children's fast-food consumption has ballooned sixfold since the 1970s, and three of every four now eat it at least weekly, said David S. Ludwig, the senior author of the paper at Children's Hospital in Boston. What interests researchers is that some children who eat it regularly aren't overweight.

``This study together with a half-dozen others raises concern that fast food could be an important cause of obesity,'' though more research is desperately needed, said Ludwig, a pediatric endocrinologist. ``We know more about zinc, which is a trace nutrient, than we do about the effect of fast food on health, which is the dominant dietary pattern among children.''

McDonald's Corp., the world's largest chain with more than 30,000 restaurants worldwide, serves 47 million customers in 100 countries each day. Burger King, the No. 2 hamburger chain is owned by closely-held investment firm Texas Pacific Group and partners. Wendy's International Inc. trails McDonald's and Burger King with 9,291 restaurants. Yum! Brands Inc. operates Kentucky Fried Chicken and Taco Bell restaurants.

Fast food restaurants have been adding healthier food choices, offering everything from salads to fruit and yogurt. More options may be in the works, they said.

``We continue to provide a wide range of options to meet our customers' varied diet and lifestyle needs,'' Wendy's spokesman Bob Bertini said. ``We have been actively testing now for some time some alternative menu options on our menu.''

Officials from other fast-food companies included in the study didn't return phone calls for comment.

To contact the reporter on this story: Michelle Fay Cortez in Minneapolis mcortez@bloomberg.net

Last Updated: June 15, 2004 16:08 EDT