Ultra-processed foods draw children’s attention — more so if they have them at home

July 31, 2024

By Ethan Chupp, UNC Gillings School Communications Fellow 

New research led by Katherine McNeel, recent Bachelor of Science in Public Health graduate from the UNC Gillings School of Global Public Health, found evidence that children paid more attention to ultra-processed food if their households had more of these foods around.

Katherine McNeel

Dr. Kyle Burger

The research, now published in JAMA Pediatrics, was first completed for McNeel’s undergraduate honors thesis under the direction of Kyle Burger, PhD, MPH, RD, professor and associate chair for research in the Gillings School’s Department of Nutrition. Findings suggest that a child’s home environment may play a key role in shaping their reactions toward ultra-processed foods from an early age.

Foods are classified based on the four-category NOVA system, developed at the University of Sao Paulo, Brazil. Unprocessed foods are obtained directly from plants or animals and do not have any added oils, sugars, salt or other substances. This category includes fresh or frozen meats and vegetables, eggs, milk, yogurt, uncooked grains and flours, pasta, nuts and seeds.

In contrast, “ultra-processed” foods are made from oils, starches, sugars and proteins derived from unprocessed foods. This category includes soda and sweetened drinks, chips, cookies, candies, hot dogs, frozen pre-cooked meals and most baked goods. Ultra-processed foods often contain flavor enhancers, colors and other additives that make them more palatable or shelf stable.

“Ultra-processed foods tend to cause people to overeat a lot more than unprocessed foods, even when you have equal amounts of sugar, fat, carbohydrates and salt,” said Burger, the senior author of this paper.

Nutrition researchers have become interested in how “attentional bias” toward food influences behaviors like overeating. Overeating is common in people whose attention is drawn to food and lingers longer. Children with greater attentional biases toward food are at greater risk for overeating and becoming overweight. Ultra-processed foods are often highly marketed and visually appealing, which may draw children’s attention even more.

In this study, McNeel and Burger’s team showed children images of ultra-processed food paired with similar photos of unprocessed food. They then tracked which image the children’s eyes were drawn to first and how long their gaze lingered on each food item. The researchers also surveyed the children’s parents on what food they had available at home and calculated the proportion of unprocessed and ultra-processed foods.

The children’s eyes tended to be drawn to the ultra-processed foods first and spend more time looking at those foods. The more ultra-processed foods there were in a child’s home, the more likely that child was to look at the ultra-processed foods first.

“These findings show how early these attentional biases may develop,” said Burger. “Even if the children aren’t consuming the foods at home, having them visible may impact how they respond to them on a physiological level. Being around ultra-processed foods at home could increase how much they want to try them outside the home.”

The most recent guidelines from the American Academy of Pediatrics emphasize obesity prevention as early as possible. The researchers conclude that changing the foods available at home could be a promising target to cultivate healthier habits in children before weight gain occurs.

Read the full paper here. 

Contact the UNC Gillings School of Global Public Health communications team at sphcomm@unc.edu.