It’s a battle played out every day in the United States: Kids persistently beg their parents for one of the sugary cereals or drive-through hamburgers they saw in a commercial while watching Saturday-morning cartoons, and eventually the worn-out parents give in, even though they know it’s unhealthy.

It has long been understood that when kids are victorious in that power struggle, it can lead to obesity and other diet-related health problems. But a new study shows that the food advertisements—which kids see in staggering numbers and which amount to $2 billion worth of ad buys per year­—may change the area of the brain that controls just how much children are apt to desire sugary cereals, candy, and fast food.

Using functional MRI technology, Dr. Amanda Bruce and a team of researchers at the University of Kansas Medical Center observed brain activity in children while watching both food advertisements and non–food related ads. According to Bruce, the more activity there was in this region, the more the child valued the food or the commercial. The results of the study, published Thursday in the Journal of Pediatrics, indicated that during the food commercials there was more activity in the portion of the brain that “encodes values and desires” than was observed during non-food advertising.

“It’s affecting kids at a physiological level, represented in the brain,” Bruce said. “It’s changing their choices in a way so that more importance is placed on taste rather than healthiness, and they’re making these decisions, more impulsive decisions, faster.”

The average kid in the United States will see an average of 4,000 food-related advertisements per year, and 98 percent of those ads are for food high in fat, sugar, or sodium, according to a 2006 study. Other behavioral studies find that children pester their parents for junk food seen in advertisements even if they know that the food is unhealthy.

Bruce says that the findings are of concern because it appears that food habits are formed in childhood and are carried over into adulthood. There are approximately 41 million obese children under the age of five worldwide, and research shows that obese children are likely to become obese adults. Children show increased activity in the reward-and-value region of the brain but do not yet have their self-control region fully developed. This results in an imbalance between the desire for unhealthy foods and the discipline needed to rein in the cravings to maintain a healthy diet. In light of that uneven brain development, a number of countries, including the United Kingdom, have banned unhealthy advertising during children’s television shows.

The new study “continues to raise questions about how ethical is it to market unhealthy foods to children particularly when we know that there’s a significant proportion of the population, both adults and kids, that struggle when carrying excess weight,” Bruce said.

This article was originally published on TakePart. Reprinted with permission.

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