Any parent who has tried to feed lunch to an uninterested toddler knows just how finicky even the smallest people can be.

A new study, published today in the December 2016 issue of Pediatrics, demonstrated how television food advertisements affect the snacking habits of preschool-aged children.

Researchers looked at 60 children ages 2 to 5 years old from New Hampshire and Vermont, according to the study, “Randomized Exposure to Food Advertisements and Eating in the Absence of Hunger Among Preschoolers.”

Adults who eat when they are tired or angry know all about EAH (eating in the absence of hunger), but they may not have realized it started so young.

Jennifer A Emond, Ph.D., assistant professor of biomedical data science at Dartmouth College, is one of the study authors. She completed data analysis and drafted the initial manuscript, and then discussed them in an interview with Healthline.com.

She also noted that the study group was quite small and the experiment needs to be replicated.

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Cue the snacking

The researchers started with the premise that preschoolers in the United States are heavily exposed to advertisements for unhealthy foods.

But whether such exposure promotes cued eating has not been documented in this age group.

So they decided to test the idea.

“An earlier study of 9- and 10-year-olds published in the Journal of Obesity showed similar results,” Emond said, but there wasn’t much research done with the preschool age group.

Here’s how the study worked.

The 60 children were provided with a healthy snack — banana and cheese cubes — when they arrived at the behavioral laboratory.

They were then randomly divided into two groups to view a 14-minute TV program complete with advertisements for either a food or a department store. Both groups saw a selection from Elmo’s World on “Sesame Street.”

All the children were given unlimited access to two snack foods to consume while viewing the TV program.

One of those snacks was the food advertised, which was Bugles corn chips. The group seeing the food ads got nine advertisements, 15 or 30 seconds each.

The other group got six advertisements, each 30 seconds long.

What researchers found was that the children who were exposed to the food advertising ate more.

“But they didn’t just eat more in general,” Emond said. “They ate more of” the advertised food.

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Unequal calories

Both groups of children helped themselves to some snacks, but not in equal amounts.

When the researchers examined the results, they found the food ad-watching group consumed 30 calories more than the other group during the 14 minutes the children spent watching Elmo.

What’s more, there was a greater consumption of the Bugles corn chips.

“It’s 30 calories more than they need,” Emond explained, “and it could add up to a couple of hundred calories a day.”

The parents reported the children watched TV about an hour a day. If they ate 30 extra calories in a quarter-hour, that’s 120 extra calories per day.

There are additional problems, Emond said.

“It’s training kids to not trust their internal hunger signals,” she explained.

“The food industry here [in the United States] is self-regulating,” Emond noted. “We need to speak out in favor of regulation.”

She pointed to a law in the United Kingdom that prevents marketing food to children, and urged parents to get involved.

“Definitions are fuzzy when it’s voluntary,” she said.

Read more: Nutritious food out of reach for 20 percent of U.S. households with children »

Ad-free programs

Acknowledging that there are no easy answers, Emond said, “I’m not saying children shouldn’t ever have snacks.”

But these energy-dense salty snacks have no nutritional value. She deals with the issue in her home by eliminating commercial television and subscribing to a service like Netflix.

Others go even further. One father told Healthline, “We think commercials are evil. So we were very restrictive in terms of what our daughter could watch.”

He told Healthline.com, “She will tell friends she’s not allowed to watch certain things. She does the same with candy.”

Outside of the lab, children present other issues around food.

“In preschool, it’s hard enough to get the kids to eat at all,” said Melinda Martin, a preschool education consultant who spent many years supervising lunchrooms.

“They would rather go out and have recess,” she told Healthline. “They just push the food around their plates.”

The EAH report concludes: “Findings suggest that food advertisement exposure may encourage obesogenic-eating behaviors among the very young.”