March 02, 2010
Dr. Barry Popkin

Dr. Barry Popkin

Children in the United States are snacking more than ever before on salty chips, candy and other junk food, according to a new University of North Carolina at Chapel Hill study led by Barry Popkin, PhD, and nutrition doctoral student Carmen Piernas.

Carmen Piernas

Carmen Piernas

The increase in snacking, which now accounts for up to 27 percent of daily caloric intake, has occurred along with a rise in childhood obesity, a health problem that has put millions of U.S. children at risk of hypertension, heart disease and diabetes.

The study, published in the March 2010 issue of the journal Health Affairs, is one of the first to look at long-term eating patterns in children, and suggests a trend in which some children snack almost continuously throughout the day.
“Our study shows that children, including very young children, eat snacks almost three times a day,” said senior author Popkin, who is the Carla Smith Chamblee Distinguished Professor of Nutrition at UNC’s Gillings School of Global Public Health.
“Such findings raise concerns that more children in the United States are moving toward a dysfunctional eating pattern, one that can lead to unhealthy weight gain and obesity,” he said.
Popkin and Piernas studied nationally representative surveys of food intake in more than 31,000 U.S. children from 1977 to 2006. The researchers zeroed in on snacking patterns and found large increases.
For example, in the first survey from 1977 to 1978, 74 percent of children aged 2 to 18 said they snacked on foods outside of regular meals. By the most recent survey, conducted from 2003 to 2006, that number had jumped to 98 percent.
“Kids still eat three meals a day, but they’re also loading up on high-calorie junk food that contains little or no nutritional value,” Popkin said.
Salty, fatty snacks, such as chips and crackers, accounted for the largest increase in the types of snacks children were eating during the three-decade period.
“Another surprising finding was that kids are eating more candy at snack time,” Piernas said. “That kind of snacking can lead not only to weight gain but to tooth decay.”
Between 1977 and 2006, children of all ages increased their caloric intake from snacks by an average of 168 calories per day, up to a total of 586 calories. The largest increase was found in children aged 2 to 6, who consumed an extra 181 calories per day during snack time compared to two decades earlier, a troubling finding that suggests an unhealthy eating pattern early in life, Popkin said.
Researchers also found that children are less likely to drink milk (which contains calcium and nutrients they need to grow properly) and are more likely to reach for fruit juice (which is almost all sugar) or other sugar-sweetened beverages, such as sports drinks, that contain many calories.
At the same time, children today are less likely to grab a fresh apple or any vegetable at snack time. The trend toward more fruit juice and less fruit and vegetables is a dangerous one because fresh produce contains fiber and lots of valuable nutrients that children need to stay healthy, Popkin said.
Consumption of desserts declined from 1977 to 2006. However, children today still snack on cake, cookies and other rich foods, and such desserts still account for a significant source of calories, Popkin noted.
An increase in calories, especially from unhealthy snack foods, plus an inactive lifestyle that includes lots of TV and computer screen time can lead to weight gain and even obesity, he said.
“Kids are eating nearly three snacks a day, and that’s too much,” Popkin said, adding that parents should:
  • try to limit snack time to once a day for children six and older.
  • make sure they stock up on plenty of healthy snack food items, including apple slices, carrots and other fruits and vegetables.
  • limit a young child’s consumption of junk food or candy and talk to older teens about the importance of a healthy diet, including snacks.

The solution to the junk food problem might require broader action, Popkin noted. For example, he said, schools should eliminate junk food sold in school vending machines or in the cafeteria, and lawmakers might need to step in and regulate or restrict advertising that sells unhealthy foods to children, a practice that has been shown to increase snacking behavior.

For more information, see
Note: Popkin can be reached at (919) 966-1732 or
UNC Gillings School of Global Public Health contact: Ramona DuBose, director of communications, (919) 966-7467 or


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