A lot of those extra calories came from sodas, which kids and teens drink when they eat out, the researchers said.
This problem is particularly acute among poorer families. Eating at fast-food restaurants is a way to get a lot of food inexpensively, Powell noted.
"Even with the general outcry that portions are too big, too high in sodium, fat and sugar, restaurants and fast food chains continue to increase the portion sizes of their foods," said Samantha Heller, an exercise physiologist and clinical nutrition coordinator at the Center for Cancer Care at Griffin Hospital in Derby, Conn.
For example, she said, Wendy's recently introduced the "Triple Baconator," which has about 1,300 calories and Subway introduced "Footlong" recession specials that have almost 1,200 calories each, she said.
"In addition, food companies incentivize buying the jumbo-sized products compared with the smaller portion," Heller added, noting that a recent study in the Archives of Internal Medicine, reported that "competition has encouraged the food industry to offer larger-size portions as a way to expand market share."
"It's no wonder kids are gaining weight and suffering from adult diseases such as high blood pressure and type 2 diabetes. We need to encourage people to cook at home more often and dispel the myth that eating at home is more expensive than eating out," she added.
"Planning menus ahead, making shopping lists and carving out time for home-cooked meals will make eating at home easier, more enjoyable and healthier for the whole family," Heller said.
For more information on healthful eating, visit the U.S. Department of Agriculture.
SOURCES: Lisa Powell, Ph.D., pr
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